1 What has changed in GDB?
2 (Organized release by release)
4 *** Changes since GDB 7.10
6 * Per-inferior thread numbers
8 Thread numbers are now per inferior instead of global. If you're
9 debugging multiple inferiors, GDB displays thread IDs using a
10 qualified INF_NUM.THR_NUM form. For example:
14 1.1 Thread 0x7ffff7fc2740 (LWP 8155) (running)
15 1.2 Thread 0x7ffff7fc1700 (LWP 8168) (running)
16 * 2.1 Thread 0x7ffff7fc2740 (LWP 8157) (running)
17 2.2 Thread 0x7ffff7fc1700 (LWP 8190) (running)
19 As consequence, thread numbers as visible in the $_thread
20 convenience variable and in Python's InferiorThread.num attribute
21 are no longer unique between inferiors.
23 GDB now maintains a second thread ID per thread, referred to as the
24 global thread ID, which is the new equivalent of thread numbers in
25 previous releases. See also $_gthread below.
27 For backwards compatibility, MI's thread IDs always refer to global
30 * Commands that accept thread IDs now accept the qualified
31 INF_NUM.THR_NUM form as well. For example:
34 [Switching to thread 2.1 (Thread 0x7ffff7fc2740 (LWP 8157))] (running)
37 * In commands that accept a list of thread IDs, you can now refer to
38 all threads of an inferior using a star wildcard. GDB accepts
39 "INF_NUM.*", to refer to all threads of inferior INF_NUM, and "*" to
40 refer to all threads of the current inferior. For example, "info
43 * You can use "info threads -gid" to display the global thread ID of
46 * The new convenience variable $_gthread holds the global number of
49 * The new convenience variable $_inferior holds the number of the
52 * Record btrace now supports non-stop mode.
54 * Support for tracepoints on aarch64-linux was added in GDBserver.
56 * The 'record instruction-history' command now indicates speculative execution
57 when using the Intel Processor Trace recording format.
59 * GDB now allows users to specify explicit locations, bypassing
60 the linespec parser. This feature is also available to GDB/MI
63 * Multi-architecture debugging is supported on AArch64 GNU/Linux.
64 GDB now is able to debug both AArch64 applications and ARM applications
67 * Support for fast tracepoints on aarch64-linux was added in GDBserver,
68 including JIT compiling fast tracepoint's conditional expression bytecode
71 * GDB now supports displaced stepping on AArch64 GNU/Linux.
73 * "info threads", "info inferiors", "info display", "info checkpoints"
74 and "maint info program-spaces" now list the corresponding items in
75 ascending ID order, for consistency with all other "info" commands.
77 * In Ada, the overloads selection menu has been enhanced to display the
78 parameter types and the return types for the matching overloaded subprograms.
82 maint set target-non-stop (on|off|auto)
83 maint show target-non-stop
84 Control whether GDB targets always operate in non-stop mode even if
85 "set non-stop" is "off". The default is "auto", meaning non-stop
86 mode is enabled if supported by the target.
89 maint show bfd-sharing
90 Control the reuse of bfd objects.
94 Control display of debugging info regarding bfd caching.
96 set remote multiprocess-extensions-packet
97 show remote multiprocess-extensions-packet
98 Set/show the use of the remote protocol multiprocess extensions.
100 set remote thread-events
101 show remote thread-events
102 Set/show the use of thread create/exit events.
104 set ada print-signatures on|off
105 show ada print-signatures"
106 Control whether parameter types and return types are displayed in overloads
107 selection menus. It is activaled (@code{on}) by default.
109 * The "disassemble" command accepts a new modifier: /s.
110 It prints mixed source+disassembly like /m with two differences:
111 - disassembled instructions are now printed in program order, and
112 - and source for all relevant files is now printed.
113 The "/m" option is now considered deprecated: its "source-centric"
114 output hasn't proved useful in practice.
116 * The "record instruction-history" command accepts a new modifier: /s.
117 It behaves exactly like /m and prints mixed source+disassembly.
119 * The "set scheduler-locking" command supports a new mode "replay".
120 It behaves like "off" in record mode and like "on" in replay mode.
122 * Support for various ROM monitors has been removed:
124 target dbug dBUG ROM monitor for Motorola ColdFire
125 target picobug Motorola picobug monitor
126 target dink32 DINK32 ROM monitor for PowerPC
127 target m32r Renesas M32R/D ROM monitor
128 target mon2000 mon2000 ROM monitor
129 target ppcbug PPCBUG ROM monitor for PowerPC
131 * Support for reading/writing memory and extracting values on architectures
132 whose memory is addressable in units of any integral multiple of 8 bits.
137 Indicates that an exec system call was executed.
139 exec-events feature in qSupported
140 The qSupported packet allows GDB to request support for exec
141 events using the new 'gdbfeature' exec-event, and the qSupported
142 response can contain the corresponding 'stubfeature'. Set and
143 show commands can be used to display whether these features are enabled.
146 Equivalent to interrupting with the ^C character, but works in
149 thread created stop reason (T05 create:...)
150 Indicates that the thread was just created and is stopped at entry.
152 thread exit stop reply (w exitcode;tid)
153 Indicates that the thread has terminated.
156 Enables/disables thread create and exit event reporting. For
157 example, this is used in non-stop mode when GDB stops a set of
158 threads and synchronously waits for the their corresponding stop
159 replies. Without exit events, if one of the threads exits, GDB
160 would hang forever not knowing that it should no longer expect a
161 stop for that same thread.
165 Indicates that there are no resumed threads left in the target (all
166 threads are stopped). The remote stub reports support for this stop
167 reply to GDB's qSupported query.
169 QCatchSyscalls:1 [;SYSNO]...
171 Enable ("QCatchSyscalls:1") or disable ("QCatchSyscalls:0")
172 catching syscalls from the inferior process.
174 syscall_entry stop reason
175 Indicates that a syscall was just called.
177 syscall_return stop reason
178 Indicates that a syscall just returned.
180 QCatchSyscalls:1 in qSupported
181 The qSupported packet may now include QCatchSyscalls:1 in the reply
182 to indicate support for catching syscalls.
184 * Extended-remote exec events
186 ** GDB now has support for exec events on extended-remote Linux targets.
187 For such targets with Linux kernels 2.5.46 and later, this enables
188 follow-exec-mode and exec catchpoints.
190 set remote exec-event-feature-packet
191 show remote exec-event-feature-packet
192 Set/show the use of the remote exec event feature.
194 * Thread names in remote protocol
196 The reply to qXfer:threads:read may now include a name attribute for each
199 * Target remote mode fork and exec events
201 ** GDB now has support for fork and exec events on target remote mode
202 Linux targets. For such targets with Linux kernels 2.5.46 and later,
203 this enables follow-fork-mode, detach-on-fork, follow-exec-mode, and
204 fork and exec catchpoints.
206 * Remote syscall events
208 ** GDB now has support for catch syscall on remote Linux targets,
209 currently enabled on x86/x86_64 architectures.
211 set remote catch-syscall-packet
212 show remote catch-syscall-packet
213 Set/show the use of the remote catch syscall feature.
217 ** The -var-set-format command now accepts the zero-hexadecimal
218 format. It outputs data in hexadecimal format with zero-padding on the
223 ** gdb.InferiorThread objects have a new attribute "global_num",
224 which refers to the thread's global thread ID. The existing
225 "num" attribute now refers to the thread's per-inferior number.
226 See "Per-inferior thread numbers" above.
227 ** gdb.InferiorThread objects have a new attribute "inferior", which
228 is the Inferior object the thread belongs to.
230 *** Changes in GDB 7.10
232 * Support for process record-replay and reverse debugging on aarch64*-linux*
233 targets has been added. GDB now supports recording of A64 instruction set
234 including advance SIMD instructions.
236 * Support for Sun's version of the "stabs" debug file format has been removed.
238 * GDB now honors the content of the file /proc/PID/coredump_filter
239 (PID is the process ID) on GNU/Linux systems. This file can be used
240 to specify the types of memory mappings that will be included in a
241 corefile. For more information, please refer to the manual page of
242 "core(5)". GDB also has a new command: "set use-coredump-filter
243 on|off". It allows to set whether GDB will read the content of the
244 /proc/PID/coredump_filter file when generating a corefile.
246 * The "info os" command on GNU/Linux can now display information on
248 "info os cpus" Listing of all cpus/cores on the system
250 * GDB has two new commands: "set serial parity odd|even|none" and
251 "show serial parity". These allows to set or show parity for the
254 * The "info source" command now displays the producer string if it was
255 present in the debug info. This typically includes the compiler version
256 and may include things like its command line arguments.
258 * The "info dll", an alias of the "info sharedlibrary" command,
259 is now available on all platforms.
261 * Directory names supplied to the "set sysroot" commands may be
262 prefixed with "target:" to tell GDB to access shared libraries from
263 the target system, be it local or remote. This replaces the prefix
264 "remote:". The default sysroot has been changed from "" to
265 "target:". "remote:" is automatically converted to "target:" for
266 backward compatibility.
268 * The system root specified by "set sysroot" will be prepended to the
269 filename of the main executable (if reported to GDB as absolute by
270 the operating system) when starting processes remotely, and when
271 attaching to already-running local or remote processes.
273 * GDB now supports automatic location and retrieval of executable
274 files from remote targets. Remote debugging can now be initiated
275 using only a "target remote" or "target extended-remote" command
276 (no "set sysroot" or "file" commands are required). See "New remote
279 * The "dump" command now supports verilog hex format.
281 * GDB now supports the vector ABI on S/390 GNU/Linux targets.
283 * On GNU/Linux, GDB and gdbserver are now able to access executable
284 and shared library files without a "set sysroot" command when
285 attaching to processes running in different mount namespaces from
286 the debugger. This makes it possible to attach to processes in
287 containers as simply as "gdb -p PID" or "gdbserver --attach PID".
288 See "New remote packets" below.
290 * The "tui reg" command now provides completion for all of the
291 available register groups, including target specific groups.
293 * The HISTSIZE environment variable is no longer read when determining
294 the size of GDB's command history. GDB now instead reads the dedicated
295 GDBHISTSIZE environment variable. Setting GDBHISTSIZE to "-1" or to "" now
296 disables truncation of command history. Non-numeric values of GDBHISTSIZE
301 ** Memory ports can now be unbuffered.
305 ** gdb.Objfile objects have a new attribute "username",
306 which is the name of the objfile as specified by the user,
307 without, for example, resolving symlinks.
308 ** You can now write frame unwinders in Python.
309 ** gdb.Type objects have a new method "optimized_out",
310 returning optimized out gdb.Value instance of this type.
311 ** gdb.Value objects have new methods "reference_value" and
312 "const_value" which return a reference to the value and a
313 "const" version of the value respectively.
317 maint print symbol-cache
318 Print the contents of the symbol cache.
320 maint print symbol-cache-statistics
321 Print statistics of symbol cache usage.
323 maint flush-symbol-cache
324 Flush the contents of the symbol cache.
328 Start branch trace recording using Branch Trace Store (BTS) format.
331 Evaluate expression by using the compiler and print result.
335 Explicit commands for enabling and disabling tui mode.
338 set mpx bound on i386 and amd64
339 Support for bound table investigation on Intel MPX enabled applications.
343 Start branch trace recording using Intel Processor Trace format.
346 Print information about branch tracing internals.
348 maint btrace packet-history
349 Print the raw branch tracing data.
351 maint btrace clear-packet-history
352 Discard the stored raw branch tracing data.
355 Discard all branch tracing data. It will be fetched and processed
356 anew by the next "record" command.
361 Renamed from "set debug dwarf2-die".
363 Renamed from "show debug dwarf2-die".
366 Renamed from "set debug dwarf2-read".
367 show debug dwarf-read
368 Renamed from "show debug dwarf2-read".
370 maint set dwarf always-disassemble
371 Renamed from "maint set dwarf2 always-disassemble".
372 maint show dwarf always-disassemble
373 Renamed from "maint show dwarf2 always-disassemble".
375 maint set dwarf max-cache-age
376 Renamed from "maint set dwarf2 max-cache-age".
377 maint show dwarf max-cache-age
378 Renamed from "maint show dwarf2 max-cache-age".
381 show debug dwarf-line
382 Control display of debugging info regarding DWARF line processing.
386 Set the maximum number of candidates to be considered during
387 completion. The default value is 200. This limit allows GDB
388 to avoid generating large completion lists, the computation of
389 which can cause the debugger to become temporarily unresponsive.
391 set history remove-duplicates
392 show history remove-duplicates
393 Control the removal of duplicate history entries.
395 maint set symbol-cache-size
396 maint show symbol-cache-size
397 Control the size of the symbol cache.
399 set|show record btrace bts buffer-size
400 Set and show the size of the ring buffer used for branch tracing in
402 The obtained size may differ from the requested size. Use "info
403 record" to see the obtained buffer size.
405 set debug linux-namespaces
406 show debug linux-namespaces
407 Control display of debugging info regarding Linux namespaces.
409 set|show record btrace pt buffer-size
410 Set and show the size of the ring buffer used for branch tracing in
411 Intel Processor Trace format.
412 The obtained size may differ from the requested size. Use "info
413 record" to see the obtained buffer size.
415 maint set|show btrace pt skip-pad
416 Set and show whether PAD packets are skipped when computing the
419 * The command 'thread apply all' can now support new option '-ascending'
420 to call its specified command for all threads in ascending order.
422 * Python/Guile scripting
424 ** GDB now supports auto-loading of Python/Guile scripts contained in the
425 special section named `.debug_gdb_scripts'.
429 qXfer:btrace-conf:read
430 Return the branch trace configuration for the current thread.
432 Qbtrace-conf:bts:size
433 Set the requested ring buffer size for branch tracing in BTS format.
436 Enable Intel Procesor Trace-based branch tracing for the current
437 process. The remote stub reports support for this packet to GDB's
441 Set the requested ring buffer size for branch tracing in Intel Processor
445 Indicates a memory breakpoint instruction was executed, irrespective
446 of whether it was GDB that planted the breakpoint or the breakpoint
447 is hardcoded in the program. This is required for correct non-stop
451 Indicates the target stopped for a hardware breakpoint. This is
452 required for correct non-stop mode operation.
455 Return information about files on the remote system.
458 Return the full absolute name of the file that was executed to
459 create a process running on the remote system.
462 Select the filesystem on which vFile: operations with filename
463 arguments will operate. This is required for GDB to be able to
464 access files on remote targets where the remote stub does not
465 share a common filesystem with the inferior(s).
468 Indicates that a fork system call was executed.
471 Indicates that a vfork system call was executed.
473 vforkdone stop reason
474 Indicates that a vfork child of the specified process has executed
475 an exec or exit, allowing the vfork parent to resume execution.
477 fork-events and vfork-events features in qSupported
478 The qSupported packet allows GDB to request support for fork and
479 vfork events using new 'gdbfeatures' fork-events and vfork-events,
480 and the qSupported response can contain the corresponding
481 'stubfeatures'. Set and show commands can be used to display
482 whether these features are enabled.
484 * Extended-remote fork events
486 ** GDB now has support for fork events on extended-remote Linux
487 targets. For targets with Linux kernels 2.5.60 and later, this
488 enables follow-fork-mode and detach-on-fork for both fork and
489 vfork, as well as fork and vfork catchpoints.
491 * The info record command now shows the recording format and the
492 branch tracing configuration for the current thread when using
493 the btrace record target.
494 For the BTS format, it shows the ring buffer size.
496 * GDB now has support for DTrace USDT (Userland Static Defined
497 Tracing) probes. The supported targets are x86_64-*-linux-gnu.
499 * GDB now supports access to vector registers on S/390 GNU/Linux
502 * Removed command line options
504 -xdb HP-UX XDB compatibility mode.
506 * Removed targets and native configurations
508 HP/PA running HP-UX hppa*-*-hpux*
509 Itanium running HP-UX ia64-*-hpux*
511 * New configure options
514 This configure option allows the user to build GDB with support for
515 Intel Processor Trace (default: auto). This requires libipt.
517 --with-libipt-prefix=PATH
518 Specify the path to the version of libipt that GDB should use.
519 $PATH/include should contain the intel-pt.h header and
520 $PATH/lib should contain the libipt.so library.
522 *** Changes in GDB 7.9.1
526 ** Xmethods can now specify a result type.
528 *** Changes in GDB 7.9
530 * GDB now supports hardware watchpoints on x86 GNU Hurd.
534 ** You can now access frame registers from Python scripts.
535 ** New attribute 'producer' for gdb.Symtab objects.
536 ** gdb.Objfile objects have a new attribute "progspace",
537 which is the gdb.Progspace object of the containing program space.
538 ** gdb.Objfile objects have a new attribute "owner".
539 ** gdb.Objfile objects have a new attribute "build_id",
540 which is the build ID generated when the file was built.
541 ** gdb.Objfile objects have a new method "add_separate_debug_file".
542 ** A new event "gdb.clear_objfiles" has been added, triggered when
543 selecting a new file to debug.
544 ** You can now add attributes to gdb.Objfile and gdb.Progspace objects.
545 ** New function gdb.lookup_objfile.
547 New events which are triggered when GDB modifies the state of the
550 ** gdb.events.inferior_call_pre: Function call is about to be made.
551 ** gdb.events.inferior_call_post: Function call has just been made.
552 ** gdb.events.memory_changed: A memory location has been altered.
553 ** gdb.events.register_changed: A register has been altered.
555 * New Python-based convenience functions:
557 ** $_caller_is(name [, number_of_frames])
558 ** $_caller_matches(regexp [, number_of_frames])
559 ** $_any_caller_is(name [, number_of_frames])
560 ** $_any_caller_matches(regexp [, number_of_frames])
562 * GDB now supports the compilation and injection of source code into
563 the inferior. GDB will use GCC 5.0 or higher built with libcc1.so
564 to compile the source code to object code, and if successful, inject
565 and execute that code within the current context of the inferior.
566 Currently the C language is supported. The commands used to
567 interface with this new feature are:
569 compile code [-raw|-r] [--] [source code]
570 compile file [-raw|-r] filename
574 demangle [-l language] [--] name
575 Demangle "name" in the specified language, or the current language
576 if elided. This command is renamed from the "maint demangle" command.
577 The latter is kept as a no-op to avoid "maint demangle" being interpreted
578 as "maint demangler-warning".
580 queue-signal signal-name-or-number
581 Queue a signal to be delivered to the thread when it is resumed.
583 add-auto-load-scripts-directory directory
584 Add entries to the list of directories from which to load auto-loaded
587 maint print user-registers
588 List all currently available "user" registers.
590 compile code [-r|-raw] [--] [source code]
591 Compile, inject, and execute in the inferior the executable object
592 code produced by compiling the provided source code.
594 compile file [-r|-raw] filename
595 Compile and inject into the inferior the executable object code
596 produced by compiling the source code stored in the filename
599 * On resume, GDB now always passes the signal the program had stopped
600 for to the thread the signal was sent to, even if the user changed
601 threads before resuming. Previously GDB would often (but not
602 always) deliver the signal to the thread that happens to be current
605 * Conversely, the "signal" command now consistently delivers the
606 requested signal to the current thread. GDB now asks for
607 confirmation if the program had stopped for a signal and the user
608 switched threads meanwhile.
610 * "breakpoint always-inserted" modes "off" and "auto" merged.
612 Now, when 'breakpoint always-inserted mode' is set to "off", GDB
613 won't remove breakpoints from the target until all threads stop,
614 even in non-stop mode. The "auto" mode has been removed, and "off"
615 is now the default mode.
619 set debug symbol-lookup
620 show debug symbol-lookup
621 Control display of debugging info regarding symbol lookup.
625 ** The -list-thread-groups command outputs an exit-code field for
626 inferiors that have exited.
630 MIPS SDE mips*-sde*-elf*
634 Support for these obsolete configurations has been removed.
636 Alpha running OSF/1 (or Tru64) alpha*-*-osf*
637 SGI Irix-5.x mips-*-irix5*
638 SGI Irix-6.x mips-*-irix6*
639 VAX running (4.2 - 4.3 Reno) BSD vax-*-bsd*
640 VAX running Ultrix vax-*-ultrix*
642 * The "dll-symbols" command, and its two aliases ("add-shared-symbol-files"
643 and "assf"), have been removed. Use the "sharedlibrary" command, or
644 its alias "share", instead.
646 *** Changes in GDB 7.8
648 * New command line options
651 This is an alias for the --data-directory option.
653 * GDB supports printing and modifying of variable length automatic arrays
654 as specified in ISO C99.
656 * The ARM simulator now supports instruction level tracing
657 with or without disassembly.
661 GDB now has support for scripting using Guile. Whether this is
662 available is determined at configure time.
663 Guile version 2.0 or greater is required.
664 Guile version 2.0.9 is well tested, earlier 2.0 versions are not.
666 * New commands (for set/show, see "New options" below)
670 Invoke CODE by passing it to the Guile interpreter.
674 Start a Guile interactive prompt (or "repl" for "read-eval-print loop").
676 info auto-load guile-scripts [regexp]
677 Print the list of automatically loaded Guile scripts.
679 * The source command is now capable of sourcing Guile scripts.
680 This feature is dependent on the debugger being built with Guile support.
684 set print symbol-loading (off|brief|full)
685 show print symbol-loading
686 Control whether to print informational messages when loading symbol
687 information for a file. The default is "full", but when debugging
688 programs with large numbers of shared libraries the amount of output
691 set guile print-stack (none|message|full)
692 show guile print-stack
693 Show a stack trace when an error is encountered in a Guile script.
695 set auto-load guile-scripts (on|off)
696 show auto-load guile-scripts
697 Control auto-loading of Guile script files.
699 maint ada set ignore-descriptive-types (on|off)
700 maint ada show ignore-descriptive-types
701 Control whether the debugger should ignore descriptive types in Ada
702 programs. The default is not to ignore the descriptive types. See
703 the user manual for more details on descriptive types and the intended
704 usage of this option.
706 set auto-connect-native-target
708 Control whether GDB is allowed to automatically connect to the
709 native target for the run, attach, etc. commands when not connected
710 to any target yet. See also "target native" below.
712 set record btrace replay-memory-access (read-only|read-write)
713 show record btrace replay-memory-access
714 Control what memory accesses are allowed during replay.
716 maint set target-async (on|off)
717 maint show target-async
718 This controls whether GDB targets operate in synchronous or
719 asynchronous mode. Normally the default is asynchronous, if it is
720 available; but this can be changed to more easily debug problems
721 occurring only in synchronous mode.
723 set mi-async (on|off)
725 Control whether MI asynchronous mode is preferred. This supersedes
726 "set target-async" of previous GDB versions.
728 * "set target-async" is deprecated as a CLI option and is now an alias
729 for "set mi-async" (only puts MI into async mode).
731 * Background execution commands (e.g., "c&", "s&", etc.) are now
732 possible ``out of the box'' if the target supports them. Previously
733 the user would need to explicitly enable the possibility with the
734 "set target-async on" command.
736 * New features in the GDB remote stub, GDBserver
738 ** New option --debug-format=option1[,option2,...] allows one to add
739 additional text to each output. At present only timestamps
740 are supported: --debug-format=timestamps.
741 Timestamps can also be turned on with the
742 "monitor set debug-format timestamps" command from GDB.
744 * The 'record instruction-history' command now starts counting instructions
745 at one. This also affects the instruction ranges reported by the
746 'record function-call-history' command when given the /i modifier.
748 * The command 'record function-call-history' supports a new modifier '/c' to
749 indent the function names based on their call stack depth.
750 The fields for the '/i' and '/l' modifier have been reordered.
751 The source line range is now prefixed with 'at'.
752 The instruction range is now prefixed with 'inst'.
753 Both ranges are now printed as '<from>, <to>' to allow copy&paste to the
754 "record instruction-history" and "list" commands.
756 * The ranges given as arguments to the 'record function-call-history' and
757 'record instruction-history' commands are now inclusive.
759 * The btrace record target now supports the 'record goto' command.
760 For locations inside the execution trace, the back trace is computed
761 based on the information stored in the execution trace.
763 * The btrace record target supports limited reverse execution and replay.
764 The target does not record data and therefore does not allow reading
767 * The "catch syscall" command now works on s390*-linux* targets.
769 * The "compare-sections" command is no longer specific to target
770 remote. It now works with all targets.
772 * All native targets are now consistently called "native".
773 Consequently, the "target child", "target GNU", "target djgpp",
774 "target procfs" (Solaris/Irix/OSF/AIX) and "target darwin-child"
775 commands have been replaced with "target native". The QNX/NTO port
776 leaves the "procfs" target in place and adds a "native" target for
777 consistency with other ports. The impact on users should be minimal
778 as these commands previously either throwed an error, or were
779 no-ops. The target's name is visible in the output of the following
780 commands: "help target", "info target", "info files", "maint print
783 * The "target native" command now connects to the native target. This
784 can be used to launch native programs even when "set
785 auto-connect-native-target" is set to off.
787 * GDB now supports access to Intel MPX registers on GNU/Linux.
789 * Support for Intel AVX-512 registers on GNU/Linux.
790 Support displaying and modifying Intel AVX-512 registers
791 $zmm0 - $zmm31 and $k0 - $k7 on GNU/Linux.
795 qXfer:btrace:read's annex
796 The qXfer:btrace:read packet supports a new annex 'delta' to read
797 branch trace incrementally.
801 ** Valid Python operations on gdb.Value objects representing
802 structs/classes invoke the corresponding overloaded operators if
804 ** New `Xmethods' feature in the Python API. Xmethods are
805 additional methods or replacements for existing methods of a C++
806 class. This feature is useful for those cases where a method
807 defined in C++ source code could be inlined or optimized out by
808 the compiler, making it unavailable to GDB.
811 PowerPC64 GNU/Linux little-endian powerpc64le-*-linux*
813 * The "dll-symbols" command, and its two aliases ("add-shared-symbol-files"
814 and "assf"), have been deprecated. Use the "sharedlibrary" command, or
815 its alias "share", instead.
817 * The commands "set remotebaud" and "show remotebaud" are no longer
818 supported. Use "set serial baud" and "show serial baud" (respectively)
823 ** A new option "-gdb-set mi-async" replaces "-gdb-set
824 target-async". The latter is left as a deprecated alias of the
825 former for backward compatibility. If the target supports it,
826 CLI background execution commands are now always possible by
827 default, independently of whether the frontend stated a
828 preference for asynchronous execution with "-gdb-set mi-async".
829 Previously "-gdb-set target-async off" affected both MI execution
830 commands and CLI execution commands.
832 *** Changes in GDB 7.7
834 * Improved support for process record-replay and reverse debugging on
835 arm*-linux* targets. Support for thumb32 and syscall instruction
836 recording has been added.
838 * GDB now supports SystemTap SDT probes on AArch64 GNU/Linux.
840 * GDB now supports Fission DWP file format version 2.
841 http://gcc.gnu.org/wiki/DebugFission
843 * New convenience function "$_isvoid", to check whether an expression
844 is void. A void expression is an expression where the type of the
845 result is "void". For example, some convenience variables may be
846 "void" when evaluated (e.g., "$_exitcode" before the execution of
847 the program being debugged; or an undefined convenience variable).
848 Another example, when calling a function whose return type is
851 * The "maintenance print objfiles" command now takes an optional regexp.
853 * The "catch syscall" command now works on arm*-linux* targets.
855 * GDB now consistently shows "<not saved>" when printing values of
856 registers the debug info indicates have not been saved in the frame
857 and there's nowhere to retrieve them from
858 (callee-saved/call-clobbered registers):
863 (gdb) info registers rax
866 Before, the former would print "<optimized out>", and the latter
867 "*value not available*".
869 * New script contrib/gdb-add-index.sh for adding .gdb_index sections
874 ** Frame filters and frame decorators have been added.
875 ** Temporary breakpoints are now supported.
876 ** Line tables representation has been added.
877 ** New attribute 'parent_type' for gdb.Field objects.
878 ** gdb.Field objects can be used as subscripts on gdb.Value objects.
879 ** New attribute 'name' for gdb.Type objects.
883 Nios II ELF nios2*-*-elf
884 Nios II GNU/Linux nios2*-*-linux
885 Texas Instruments MSP430 msp430*-*-elf
887 * Removed native configurations
889 Support for these a.out NetBSD and OpenBSD obsolete configurations has
890 been removed. ELF variants of these configurations are kept supported.
892 arm*-*-netbsd* but arm*-*-netbsdelf* is kept supported.
893 i[34567]86-*-netbsd* but i[34567]86-*-netbsdelf* is kept supported.
894 i[34567]86-*-openbsd[0-2].* but i[34567]86-*-openbsd* is kept supported.
895 i[34567]86-*-openbsd3.[0-3]
896 m68*-*-netbsd* but m68*-*-netbsdelf* is kept supported.
897 sparc-*-netbsd* but sparc-*-netbsdelf* is kept supported.
898 vax-*-netbsd* but vax-*-netbsdelf* is kept supported.
902 Like "catch throw", but catches a re-thrown exception.
904 Renamed from old "maint check-symtabs".
906 Perform consistency checks on symtabs.
908 Expand symtabs matching an optional regexp.
911 Display the details of GDB configure-time options.
913 maint set|show per-command
914 maint set|show per-command space
915 maint set|show per-command time
916 maint set|show per-command symtab
917 Enable display of per-command gdb resource usage.
919 remove-symbol-file FILENAME
920 remove-symbol-file -a ADDRESS
921 Remove a symbol file added via add-symbol-file. The file to remove
922 can be identified by its filename or by an address that lies within
923 the boundaries of this symbol file in memory.
926 info exceptions REGEXP
927 Display the list of Ada exceptions defined in the program being
928 debugged. If provided, only the exceptions whose names match REGEXP
933 set debug symfile off|on
935 Control display of debugging info regarding reading symbol files and
936 symbol tables within those files
938 set print raw frame-arguments
939 show print raw frame-arguments
940 Set/show whether to print frame arguments in raw mode,
941 disregarding any defined pretty-printers.
943 set remote trace-status-packet
944 show remote trace-status-packet
945 Set/show the use of remote protocol qTStatus packet.
949 Control display of debugging messages related to Nios II targets.
953 Control whether target-assisted range stepping is enabled.
955 set startup-with-shell
956 show startup-with-shell
957 Specifies whether Unix child processes are started via a shell or
962 Use the target memory cache for accesses to the code segment. This
963 improves performance of remote debugging (particularly disassembly).
965 * You can now use a literal value 'unlimited' for options that
966 interpret 0 or -1 as meaning "unlimited". E.g., "set
967 trace-buffer-size unlimited" is now an alias for "set
968 trace-buffer-size -1" and "set height unlimited" is now an alias for
971 * The "set debug symtab-create" debugging option of GDB has been changed to
972 accept a verbosity level. 0 means "off", 1 provides basic debugging
973 output, and values of 2 or greater provides more verbose output.
975 * New command-line options
977 Display the details of GDB configure-time options.
979 * The command 'tsave' can now support new option '-ctf' to save trace
980 buffer in Common Trace Format.
982 * Newly installed $prefix/bin/gcore acts as a shell interface for the
985 * GDB now implements the the C++ 'typeid' operator.
987 * The new convenience variable $_exception holds the exception being
988 thrown or caught at an exception-related catchpoint.
990 * The exception-related catchpoints, like "catch throw", now accept a
991 regular expression which can be used to filter exceptions by type.
993 * The new convenience variable $_exitsignal is automatically set to
994 the terminating signal number when the program being debugged dies
995 due to an uncaught signal.
999 ** All MI commands now accept an optional "--language" option.
1000 Support for this feature can be verified by using the "-list-features"
1001 command, which should contain "language-option".
1003 ** The new command -info-gdb-mi-command allows the user to determine
1004 whether a GDB/MI command is supported or not.
1006 ** The "^error" result record returned when trying to execute an undefined
1007 GDB/MI command now provides a variable named "code" whose content is the
1008 "undefined-command" error code. Support for this feature can be verified
1009 by using the "-list-features" command, which should contain
1010 "undefined-command-error-code".
1012 ** The -trace-save MI command can optionally save trace buffer in Common
1015 ** The new command -dprintf-insert sets a dynamic printf breakpoint.
1017 ** The command -data-list-register-values now accepts an optional
1018 "--skip-unavailable" option. When used, only the available registers
1021 ** The new command -trace-frame-collected dumps collected variables,
1022 computed expressions, tvars, memory and registers in a traceframe.
1024 ** The commands -stack-list-locals, -stack-list-arguments and
1025 -stack-list-variables now accept an option "--skip-unavailable".
1026 When used, only the available locals or arguments are displayed.
1028 ** The -exec-run command now accepts an optional "--start" option.
1029 When used, the command follows the same semantics as the "start"
1030 command, stopping the program's execution at the start of its
1031 main subprogram. Support for this feature can be verified using
1032 the "-list-features" command, which should contain
1033 "exec-run-start-option".
1035 ** The new commands -catch-assert and -catch-exceptions insert
1036 catchpoints stopping the program when Ada exceptions are raised.
1038 ** The new command -info-ada-exceptions provides the equivalent of
1039 the new "info exceptions" command.
1041 * New system-wide configuration scripts
1042 A GDB installation now provides scripts suitable for use as system-wide
1043 configuration scripts for the following systems:
1047 * GDB now supports target-assigned range stepping with remote targets.
1048 This improves the performance of stepping source lines by reducing
1049 the number of control packets from/to GDB. See "New remote packets"
1052 * GDB now understands the element 'tvar' in the XML traceframe info.
1053 It has the id of the collected trace state variables.
1055 * On S/390 targets that provide the transactional-execution feature,
1056 the program interruption transaction diagnostic block (TDB) is now
1057 represented as a number of additional "registers" in GDB.
1059 * New remote packets
1063 The vCont packet supports a new 'r' action, that tells the remote
1064 stub to step through an address range itself, without GDB
1065 involvemement at each single-step.
1067 qXfer:libraries-svr4:read's annex
1068 The previously unused annex of the qXfer:libraries-svr4:read packet
1069 is now used to support passing an argument list. The remote stub
1070 reports support for this argument list to GDB's qSupported query.
1071 The defined arguments are "start" and "prev", used to reduce work
1072 necessary for library list updating, resulting in significant
1075 * New features in the GDB remote stub, GDBserver
1077 ** GDBserver now supports target-assisted range stepping. Currently
1078 enabled on x86/x86_64 GNU/Linux targets.
1080 ** GDBserver now adds element 'tvar' in the XML in the reply to
1081 'qXfer:traceframe-info:read'. It has the id of the collected
1082 trace state variables.
1084 ** GDBserver now supports hardware watchpoints on the MIPS GNU/Linux
1087 * New 'z' formatter for printing and examining memory, this displays the
1088 value as hexadecimal zero padded on the left to the size of the type.
1090 * GDB can now use Windows x64 unwinding data.
1092 * The "set remotebaud" command has been replaced by "set serial baud".
1093 Similarly, "show remotebaud" has been replaced by "show serial baud".
1094 The "set remotebaud" and "show remotebaud" commands are still available
1095 to provide backward compatibility with older versions of GDB.
1097 *** Changes in GDB 7.6
1099 * Target record has been renamed to record-full.
1100 Record/replay is now enabled with the "record full" command.
1101 This also affects settings that are associated with full record/replay
1102 that have been moved from "set/show record" to "set/show record full":
1104 set|show record full insn-number-max
1105 set|show record full stop-at-limit
1106 set|show record full memory-query
1108 * A new record target "record-btrace" has been added. The new target
1109 uses hardware support to record the control-flow of a process. It
1110 does not support replaying the execution, but it implements the
1111 below new commands for investigating the recorded execution log.
1112 This new recording method can be enabled using:
1116 The "record-btrace" target is only available on Intel Atom processors
1117 and requires a Linux kernel 2.6.32 or later.
1119 * Two new commands have been added for record/replay to give information
1120 about the recorded execution without having to replay the execution.
1121 The commands are only supported by "record btrace".
1123 record instruction-history prints the execution history at
1124 instruction granularity
1126 record function-call-history prints the execution history at
1127 function granularity
1129 * New native configurations
1131 ARM AArch64 GNU/Linux aarch64*-*-linux-gnu
1132 FreeBSD/powerpc powerpc*-*-freebsd
1133 x86_64/Cygwin x86_64-*-cygwin*
1134 Tilera TILE-Gx GNU/Linux tilegx*-*-linux-gnu
1138 ARM AArch64 aarch64*-*-elf
1139 ARM AArch64 GNU/Linux aarch64*-*-linux
1140 Lynx 178 PowerPC powerpc-*-lynx*178
1141 x86_64/Cygwin x86_64-*-cygwin*
1142 Tilera TILE-Gx GNU/Linux tilegx*-*-linux
1144 * If the configured location of system.gdbinit file (as given by the
1145 --with-system-gdbinit option at configure time) is in the
1146 data-directory (as specified by --with-gdb-datadir at configure
1147 time) or in one of its subdirectories, then GDB will look for the
1148 system-wide init file in the directory specified by the
1149 --data-directory command-line option.
1151 * New command line options:
1153 -nh Disables auto-loading of ~/.gdbinit, but still executes all the
1154 other initialization files, unlike -nx which disables all of them.
1156 * Removed command line options
1158 -epoch This was used by the gdb mode in Epoch, an ancient fork of
1161 * The 'ptype' and 'whatis' commands now accept an argument to control
1164 * 'info proc' now works on some core files.
1168 ** Vectors can be created with gdb.Type.vector.
1170 ** Python's atexit.register now works in GDB.
1172 ** Types can be pretty-printed via a Python API.
1174 ** Python 3 is now supported (in addition to Python 2.4 or later)
1176 ** New class gdb.Architecture exposes GDB's internal representation
1177 of architecture in the Python API.
1179 ** New method Frame.architecture returns the gdb.Architecture object
1180 corresponding to the frame's architecture.
1182 * New Python-based convenience functions:
1184 ** $_memeq(buf1, buf2, length)
1185 ** $_streq(str1, str2)
1187 ** $_regex(str, regex)
1189 * The 'cd' command now defaults to using '~' (the home directory) if not
1192 * The C++ ABI now defaults to the GNU v3 ABI. This has been the
1193 default for GCC since November 2000.
1195 * The command 'forward-search' can now be abbreviated as 'fo'.
1197 * The command 'info tracepoints' can now display 'installed on target'
1198 or 'not installed on target' for each non-pending location of tracepoint.
1200 * New configure options
1202 --enable-libmcheck/--disable-libmcheck
1203 By default, development versions are built with -lmcheck on hosts
1204 that support it, in order to help track memory corruption issues.
1205 Release versions, on the other hand, are built without -lmcheck
1206 by default. The --enable-libmcheck/--disable-libmcheck configure
1207 options allow the user to override that default.
1208 --with-babeltrace/--with-babeltrace-include/--with-babeltrace-lib
1209 This configure option allows the user to build GDB with
1210 libbabeltrace using which GDB can read Common Trace Format data.
1212 * New commands (for set/show, see "New options" below)
1215 Catch signals. This is similar to "handle", but allows commands and
1216 conditions to be attached.
1219 List the BFDs known to GDB.
1221 python-interactive [command]
1223 Start a Python interactive prompt, or evaluate the optional command
1224 and print the result of expressions.
1227 "py" is a new alias for "python".
1229 enable type-printer [name]...
1230 disable type-printer [name]...
1231 Enable or disable type printers.
1235 ** For the Renesas Super-H architecture, the "regs" command has been removed
1236 (has been deprecated in GDB 7.5), and "info all-registers" should be used
1241 set print type methods (on|off)
1242 show print type methods
1243 Control whether method declarations are displayed by "ptype".
1244 The default is to show them.
1246 set print type typedefs (on|off)
1247 show print type typedefs
1248 Control whether typedef definitions are displayed by "ptype".
1249 The default is to show them.
1251 set filename-display basename|relative|absolute
1252 show filename-display
1253 Control the way in which filenames is displayed.
1254 The default is "relative", which preserves previous behavior.
1256 set trace-buffer-size
1257 show trace-buffer-size
1258 Request target to change the size of trace buffer.
1260 set remote trace-buffer-size-packet auto|on|off
1261 show remote trace-buffer-size-packet
1262 Control the use of the remote protocol `QTBuffer:size' packet.
1266 Control display of debugging messages related to ARM AArch64.
1269 set debug coff-pe-read
1270 show debug coff-pe-read
1271 Control display of debugging messages related to reading of COFF/PE
1276 Control display of debugging messages related to Mach-O symbols
1279 set debug notification
1280 show debug notification
1281 Control display of debugging info for async remote notification.
1285 ** Command parameter changes are now notified using new async record
1286 "=cmd-param-changed".
1287 ** Trace frame changes caused by command "tfind" are now notified using
1288 new async record "=traceframe-changed".
1289 ** The creation, deletion and modification of trace state variables
1290 are now notified using new async records "=tsv-created",
1291 "=tsv-deleted" and "=tsv-modified".
1292 ** The start and stop of process record are now notified using new
1293 async record "=record-started" and "=record-stopped".
1294 ** Memory changes are now notified using new async record
1296 ** The data-disassemble command response will include a "fullname" field
1297 containing the absolute file name when source has been requested.
1298 ** New optional parameter COUNT added to the "-data-write-memory-bytes"
1299 command, to allow pattern filling of memory areas.
1300 ** New commands "-catch-load"/"-catch-unload" added for intercepting
1301 library load/unload events.
1302 ** The response to breakpoint commands and breakpoint async records
1303 includes an "installed" field containing a boolean state about each
1304 non-pending tracepoint location is whether installed on target or not.
1305 ** Output of the "-trace-status" command includes a "trace-file" field
1306 containing the name of the trace file being examined. This field is
1307 optional, and only present when examining a trace file.
1308 ** The "fullname" field is now always present along with the "file" field,
1309 even if the file cannot be found by GDB.
1311 * GDB now supports the "mini debuginfo" section, .gnu_debugdata.
1312 You must have the LZMA library available when configuring GDB for this
1313 feature to be enabled. For more information, see:
1314 http://fedoraproject.org/wiki/Features/MiniDebugInfo
1316 * New remote packets
1319 Set the size of trace buffer. The remote stub reports support for this
1320 packet to gdb's qSupported query.
1323 Enable Branch Trace Store (BTS)-based branch tracing for the current
1324 thread. The remote stub reports support for this packet to gdb's
1328 Disable branch tracing for the current thread. The remote stub reports
1329 support for this packet to gdb's qSupported query.
1332 Read the traced branches for the current thread. The remote stub
1333 reports support for this packet to gdb's qSupported query.
1335 *** Changes in GDB 7.5
1337 * GDB now supports x32 ABI. Visit <http://sites.google.com/site/x32abi/>
1338 for more x32 ABI info.
1340 * GDB now supports access to MIPS DSP registers on Linux targets.
1342 * GDB now supports debugging microMIPS binaries.
1344 * The "info os" command on GNU/Linux can now display information on
1345 several new classes of objects managed by the operating system:
1346 "info os procgroups" lists process groups
1347 "info os files" lists file descriptors
1348 "info os sockets" lists internet-domain sockets
1349 "info os shm" lists shared-memory regions
1350 "info os semaphores" lists semaphores
1351 "info os msg" lists message queues
1352 "info os modules" lists loaded kernel modules
1354 * GDB now has support for SDT (Static Defined Tracing) probes. Currently,
1355 the only implemented backend is for SystemTap probes (<sys/sdt.h>). You
1356 can set a breakpoint using the new "-probe, "-pstap" or "-probe-stap"
1357 options and inspect the probe arguments using the new $_probe_arg family
1358 of convenience variables. You can obtain more information about SystemTap
1359 in <http://sourceware.org/systemtap/>.
1361 * GDB now supports reversible debugging on ARM, it allows you to
1362 debug basic ARM and THUMB instructions, and provides
1363 record/replay support.
1365 * The option "symbol-reloading" has been deleted as it is no longer used.
1369 ** GDB commands implemented in Python can now be put in command class
1372 ** The "maint set python print-stack on|off" is now deleted.
1374 ** A new class, gdb.printing.FlagEnumerationPrinter, can be used to
1375 apply "flag enum"-style pretty-printing to any enum.
1377 ** gdb.lookup_symbol can now work when there is no current frame.
1379 ** gdb.Symbol now has a 'line' attribute, holding the line number in
1380 the source at which the symbol was defined.
1382 ** gdb.Symbol now has the new attribute 'needs_frame' and the new
1383 method 'value'. The former indicates whether the symbol needs a
1384 frame in order to compute its value, and the latter computes the
1387 ** A new method 'referenced_value' on gdb.Value objects which can
1388 dereference pointer as well as C++ reference values.
1390 ** New methods 'global_block' and 'static_block' on gdb.Symtab objects
1391 which return the global and static blocks (as gdb.Block objects),
1392 of the underlying symbol table, respectively.
1394 ** New function gdb.find_pc_line which returns the gdb.Symtab_and_line
1395 object associated with a PC value.
1397 ** gdb.Symtab_and_line has new attribute 'last' which holds the end
1398 of the address range occupied by code for the current source line.
1400 * Go language support.
1401 GDB now supports debugging programs written in the Go programming
1404 * GDBserver now supports stdio connections.
1405 E.g. (gdb) target remote | ssh myhost gdbserver - hello
1407 * The binary "gdbtui" can no longer be built or installed.
1408 Use "gdb -tui" instead.
1410 * GDB will now print "flag" enums specially. A flag enum is one where
1411 all the enumerator values have no bits in common when pairwise
1412 "and"ed. When printing a value whose type is a flag enum, GDB will
1413 show all the constants, e.g., for enum E { ONE = 1, TWO = 2}:
1414 (gdb) print (enum E) 3
1417 * The filename part of a linespec will now match trailing components
1418 of a source file name. For example, "break gcc/expr.c:1000" will
1419 now set a breakpoint in build/gcc/expr.c, but not
1420 build/libcpp/expr.c.
1422 * The "info proc" and "generate-core-file" commands will now also
1423 work on remote targets connected to GDBserver on Linux.
1425 * The command "info catch" has been removed. It has been disabled
1426 since December 2007.
1428 * The "catch exception" and "catch assert" commands now accept
1429 a condition at the end of the command, much like the "break"
1430 command does. For instance:
1432 (gdb) catch exception Constraint_Error if Barrier = True
1434 Previously, it was possible to add a condition to such catchpoints,
1435 but it had to be done as a second step, after the catchpoint had been
1436 created, using the "condition" command.
1438 * The "info static-tracepoint-marker" command will now also work on
1439 native Linux targets with in-process agent.
1441 * GDB can now set breakpoints on inlined functions.
1443 * The .gdb_index section has been updated to include symbols for
1444 inlined functions. GDB will ignore older .gdb_index sections by
1445 default, which could cause symbol files to be loaded more slowly
1446 until their .gdb_index sections can be recreated. The new command
1447 "set use-deprecated-index-sections on" will cause GDB to use any older
1448 .gdb_index sections it finds. This will restore performance, but the
1449 ability to set breakpoints on inlined functions will be lost in symbol
1450 files with older .gdb_index sections.
1452 The .gdb_index section has also been updated to record more information
1453 about each symbol. This speeds up the "info variables", "info functions"
1454 and "info types" commands when used with programs having the .gdb_index
1455 section, as well as speeding up debugging with shared libraries using
1456 the .gdb_index section.
1458 * Ada support for GDB/MI Variable Objects has been added.
1460 * GDB can now support 'breakpoint always-inserted mode' in 'record'
1465 ** New command -info-os is the MI equivalent of "info os".
1467 ** Output logs ("set logging" and related) now include MI output.
1471 ** "set use-deprecated-index-sections on|off"
1472 "show use-deprecated-index-sections on|off"
1473 Controls the use of deprecated .gdb_index sections.
1475 ** "catch load" and "catch unload" can be used to stop when a shared
1476 library is loaded or unloaded, respectively.
1478 ** "enable count" can be used to auto-disable a breakpoint after
1481 ** "info vtbl" can be used to show the virtual method tables for
1482 C++ and Java objects.
1484 ** "explore" and its sub commands "explore value" and "explore type"
1485 can be used to recursively explore values and types of
1486 expressions. These commands are available only if GDB is
1487 configured with '--with-python'.
1489 ** "info auto-load" shows status of all kinds of auto-loaded files,
1490 "info auto-load gdb-scripts" shows status of auto-loading GDB canned
1491 sequences of commands files, "info auto-load python-scripts"
1492 shows status of auto-loading Python script files,
1493 "info auto-load local-gdbinit" shows status of loading init file
1494 (.gdbinit) from current directory and "info auto-load libthread-db" shows
1495 status of inferior specific thread debugging shared library loading.
1497 ** "info auto-load-scripts", "set auto-load-scripts on|off"
1498 and "show auto-load-scripts" commands have been deprecated, use their
1499 "info auto-load python-scripts", "set auto-load python-scripts on|off"
1500 and "show auto-load python-scripts" counterparts instead.
1502 ** "dprintf location,format,args..." creates a dynamic printf, which
1503 is basically a breakpoint that does a printf and immediately
1504 resumes your program's execution, so it is like a printf that you
1505 can insert dynamically at runtime instead of at compiletime.
1507 ** "set print symbol"
1509 Controls whether GDB attempts to display the symbol, if any,
1510 corresponding to addresses it prints. This defaults to "on", but
1511 you can set it to "off" to restore GDB's previous behavior.
1513 * Deprecated commands
1515 ** For the Renesas Super-H architecture, the "regs" command has been
1516 deprecated, and "info all-registers" should be used instead.
1520 Renesas RL78 rl78-*-elf
1521 HP OpenVMS ia64 ia64-hp-openvms*
1523 * GDBserver supports evaluation of breakpoint conditions. When
1524 support is advertised by GDBserver, GDB may be told to send the
1525 breakpoint conditions in bytecode form to GDBserver. GDBserver
1526 will only report the breakpoint trigger to GDB when its condition
1531 set mips compression
1532 show mips compression
1533 Select the compressed ISA encoding used in functions that have no symbol
1534 information available. The encoding can be set to either of:
1537 and is updated automatically from ELF file flags if available.
1539 set breakpoint condition-evaluation
1540 show breakpoint condition-evaluation
1541 Control whether breakpoint conditions are evaluated by GDB ("host") or by
1542 GDBserver ("target"). Default option "auto" chooses the most efficient
1544 This option can improve debugger efficiency depending on the speed of the
1548 Disable auto-loading globally.
1551 Show auto-loading setting of all kinds of auto-loaded files.
1553 set auto-load gdb-scripts on|off
1554 show auto-load gdb-scripts
1555 Control auto-loading of GDB canned sequences of commands files.
1557 set auto-load python-scripts on|off
1558 show auto-load python-scripts
1559 Control auto-loading of Python script files.
1561 set auto-load local-gdbinit on|off
1562 show auto-load local-gdbinit
1563 Control loading of init file (.gdbinit) from current directory.
1565 set auto-load libthread-db on|off
1566 show auto-load libthread-db
1567 Control auto-loading of inferior specific thread debugging shared library.
1569 set auto-load scripts-directory <dir1>[:<dir2>...]
1570 show auto-load scripts-directory
1571 Set a list of directories from which to load auto-loaded scripts.
1572 Automatically loaded Python scripts and GDB scripts are located in one
1573 of the directories listed by this option.
1574 The delimiter (':' above) may differ according to the host platform.
1576 set auto-load safe-path <dir1>[:<dir2>...]
1577 show auto-load safe-path
1578 Set a list of directories from which it is safe to auto-load files.
1579 The delimiter (':' above) may differ according to the host platform.
1581 set debug auto-load on|off
1582 show debug auto-load
1583 Control display of debugging info for auto-loading the files above.
1585 set dprintf-style gdb|call|agent
1587 Control the way in which a dynamic printf is performed; "gdb"
1588 requests a GDB printf command, while "call" causes dprintf to call a
1589 function in the inferior. "agent" requests that the target agent
1590 (such as GDBserver) do the printing.
1592 set dprintf-function <expr>
1593 show dprintf-function
1594 set dprintf-channel <expr>
1595 show dprintf-channel
1596 Set the function and optional first argument to the call when using
1597 the "call" style of dynamic printf.
1599 set disconnected-dprintf on|off
1600 show disconnected-dprintf
1601 Control whether agent-style dynamic printfs continue to be in effect
1602 after GDB disconnects.
1604 * New configure options
1606 --with-auto-load-dir
1607 Configure default value for the 'set auto-load scripts-directory'
1608 setting above. It defaults to '$debugdir:$datadir/auto-load',
1609 $debugdir representing global debugging info directories (available
1610 via 'show debug-file-directory') and $datadir representing GDB's data
1611 directory (available via 'show data-directory').
1613 --with-auto-load-safe-path
1614 Configure default value for the 'set auto-load safe-path' setting
1615 above. It defaults to the --with-auto-load-dir setting.
1617 --without-auto-load-safe-path
1618 Set 'set auto-load safe-path' to '/', effectively disabling this
1621 * New remote packets
1623 z0/z1 conditional breakpoints extension
1625 The z0/z1 breakpoint insertion packets have been extended to carry
1626 a list of conditional expressions over to the remote stub depending on the
1627 condition evaluation mode. The use of this extension can be controlled
1628 via the "set remote conditional-breakpoints-packet" command.
1632 Specify the signals which the remote stub may pass to the debugged
1633 program without GDB involvement.
1635 * New command line options
1637 --init-command=FILE, -ix Like --command, -x but execute it
1638 before loading inferior.
1639 --init-eval-command=COMMAND, -iex Like --eval-command=COMMAND, -ex but
1640 execute it before loading inferior.
1642 *** Changes in GDB 7.4
1644 * GDB now handles ambiguous linespecs more consistently; the existing
1645 FILE:LINE support has been expanded to other types of linespecs. A
1646 breakpoint will now be set on all matching locations in all
1647 inferiors, and locations will be added or removed according to
1650 * GDB now allows you to skip uninteresting functions and files when
1651 stepping with the "skip function" and "skip file" commands.
1653 * GDB has two new commands: "set remote hardware-watchpoint-length-limit"
1654 and "show remote hardware-watchpoint-length-limit". These allows to
1655 set or show the maximum length limit (in bytes) of a remote
1656 target hardware watchpoint.
1658 This allows e.g. to use "unlimited" hardware watchpoints with the
1659 gdbserver integrated in Valgrind version >= 3.7.0. Such Valgrind
1660 watchpoints are slower than real hardware watchpoints but are
1661 significantly faster than gdb software watchpoints.
1665 ** The register_pretty_printer function in module gdb.printing now takes
1666 an optional `replace' argument. If True, the new printer replaces any
1669 ** The "maint set python print-stack on|off" command has been
1670 deprecated and will be deleted in GDB 7.5.
1671 A new command: "set python print-stack none|full|message" has
1672 replaced it. Additionally, the default for "print-stack" is
1673 now "message", which just prints the error message without
1676 ** A prompt substitution hook (prompt_hook) is now available to the
1679 ** A new Python module, gdb.prompt has been added to the GDB Python
1680 modules library. This module provides functionality for
1681 escape sequences in prompts (used by set/show
1682 extended-prompt). These escape sequences are replaced by their
1683 corresponding value.
1685 ** Python commands and convenience-functions located in
1686 'data-directory'/python/gdb/command and
1687 'data-directory'/python/gdb/function are now automatically loaded
1690 ** Blocks now provide four new attributes. global_block and
1691 static_block will return the global and static blocks
1692 respectively. is_static and is_global are boolean attributes
1693 that indicate if the block is one of those two types.
1695 ** Symbols now provide the "type" attribute, the type of the symbol.
1697 ** The "gdb.breakpoint" function has been deprecated in favor of
1700 ** A new class "gdb.FinishBreakpoint" is provided to catch the return
1701 of a function. This class is based on the "finish" command
1702 available in the CLI.
1704 ** Type objects for struct and union types now allow access to
1705 the fields using standard Python dictionary (mapping) methods.
1706 For example, "some_type['myfield']" now works, as does
1707 "some_type.items()".
1709 ** A new event "gdb.new_objfile" has been added, triggered by loading a
1712 ** A new function, "deep_items" has been added to the gdb.types
1713 module in the GDB Python modules library. This function returns
1714 an iterator over the fields of a struct or union type. Unlike
1715 the standard Python "iteritems" method, it will recursively traverse
1716 any anonymous fields.
1720 ** "*stopped" events can report several new "reason"s, such as
1723 ** Breakpoint changes are now notified using new async records, like
1724 "=breakpoint-modified".
1726 ** New command -ada-task-info.
1728 * libthread-db-search-path now supports two special values: $sdir and $pdir.
1729 $sdir specifies the default system locations of shared libraries.
1730 $pdir specifies the directory where the libpthread used by the application
1733 GDB no longer looks in $sdir and $pdir after it has searched the directories
1734 mentioned in libthread-db-search-path. If you want to search those
1735 directories, they must be specified in libthread-db-search-path.
1736 The default value of libthread-db-search-path on GNU/Linux and Solaris
1737 systems is now "$sdir:$pdir".
1739 $pdir is not supported by gdbserver, it is currently ignored.
1740 $sdir is supported by gdbserver.
1742 * New configure option --with-iconv-bin.
1743 When using the internationalization support like the one in the GNU C
1744 library, GDB will invoke the "iconv" program to get a list of supported
1745 character sets. If this program lives in a non-standard location, one can
1746 use this option to specify where to find it.
1748 * When natively debugging programs on PowerPC BookE processors running
1749 a Linux kernel version 2.6.34 or later, GDB supports masked hardware
1750 watchpoints, which specify a mask in addition to an address to watch.
1751 The mask specifies that some bits of an address (the bits which are
1752 reset in the mask) should be ignored when matching the address accessed
1753 by the inferior against the watchpoint address. See the "PowerPC Embedded"
1754 section in the user manual for more details.
1756 * The new option --once causes GDBserver to stop listening for connections once
1757 the first connection is made. The listening port used by GDBserver will
1758 become available after that.
1760 * New commands "info macros" and "alias" have been added.
1762 * New function parameters suffix @entry specifies value of function parameter
1763 at the time the function got called. Entry values are available only since
1769 "!" is now an alias of the "shell" command.
1770 Note that no space is needed between "!" and SHELL COMMAND.
1774 watch EXPRESSION mask MASK_VALUE
1775 The watch command now supports the mask argument which allows creation
1776 of masked watchpoints, if the current architecture supports this feature.
1778 info auto-load-scripts [REGEXP]
1779 This command was formerly named "maintenance print section-scripts".
1780 It is now generally useful and is no longer a maintenance-only command.
1782 info macro [-all] [--] MACRO
1783 The info macro command has new options `-all' and `--'. The first for
1784 printing all definitions of a macro. The second for explicitly specifying
1785 the end of arguments and the beginning of the macro name in case the macro
1786 name starts with a hyphen.
1788 collect[/s] EXPRESSIONS
1789 The tracepoint collect command now takes an optional modifier "/s"
1790 that directs it to dereference pointer-to-character types and
1791 collect the bytes of memory up to a zero byte. The behavior is
1792 similar to what you see when you use the regular print command on a
1793 string. An optional integer following the "/s" sets a bound on the
1794 number of bytes that will be collected.
1797 The trace start command now interprets any supplied arguments as a
1798 note to be recorded with the trace run, with an effect similar to
1799 setting the variable trace-notes.
1802 The trace stop command now interprets any arguments as a note to be
1803 mentioned along with the tstatus report that the trace was stopped
1804 with a command. The effect is similar to setting the variable
1807 * Tracepoints can now be enabled and disabled at any time after a trace
1808 experiment has been started using the standard "enable" and "disable"
1809 commands. It is now possible to start a trace experiment with no enabled
1810 tracepoints; GDB will display a warning, but will allow the experiment to
1811 begin, assuming that tracepoints will be enabled as needed while the trace
1814 * Fast tracepoints on 32-bit x86-architectures can now be placed at
1815 locations with 4-byte instructions, when they were previously
1816 limited to locations with instructions of 5 bytes or longer.
1820 set debug dwarf2-read
1821 show debug dwarf2-read
1822 Turns on or off display of debugging messages related to reading
1823 DWARF debug info. The default is off.
1825 set debug symtab-create
1826 show debug symtab-create
1827 Turns on or off display of debugging messages related to symbol table
1828 creation. The default is off.
1831 show extended-prompt
1832 Set the GDB prompt, and allow escape sequences to be inserted to
1833 display miscellaneous information (see 'help set extended-prompt'
1834 for the list of sequences). This prompt (and any information
1835 accessed through the escape sequences) is updated every time the
1836 prompt is displayed.
1838 set print entry-values (both|compact|default|if-needed|no|only|preferred)
1839 show print entry-values
1840 Set printing of frame argument values at function entry. In some cases
1841 GDB can determine the value of function argument which was passed by the
1842 function caller, even if the value was modified inside the called function.
1844 set debug entry-values
1845 show debug entry-values
1846 Control display of debugging info for determining frame argument values at
1847 function entry and virtual tail call frames.
1849 set basenames-may-differ
1850 show basenames-may-differ
1851 Set whether a source file may have multiple base names.
1852 (A "base name" is the name of a file with the directory part removed.
1853 Example: The base name of "/home/user/hello.c" is "hello.c".)
1854 If set, GDB will canonicalize file names (e.g., expand symlinks)
1855 before comparing them. Canonicalization is an expensive operation,
1856 but it allows the same file be known by more than one base name.
1857 If not set (the default), all source files are assumed to have just
1858 one base name, and gdb will do file name comparisons more efficiently.
1864 Set a user name and notes for the current and any future trace runs.
1865 This is useful for long-running and/or disconnected traces, to
1866 inform others (or yourself) as to who is running the trace, supply
1867 contact information, or otherwise explain what is going on.
1869 set trace-stop-notes
1870 show trace-stop-notes
1871 Set a note attached to the trace run, that is displayed when the
1872 trace has been stopped by a tstop command. This is useful for
1873 instance as an explanation, if you are stopping a trace run that was
1874 started by someone else.
1876 * New remote packets
1880 Dynamically enable a tracepoint in a started trace experiment.
1884 Dynamically disable a tracepoint in a started trace experiment.
1888 Set the user and notes of the trace run.
1892 Query the current status of a tracepoint.
1896 Query the minimum length of instruction at which a fast tracepoint may
1899 * Dcache size (number of lines) and line-size are now runtime-configurable
1900 via "set dcache line" and "set dcache line-size" commands.
1904 Texas Instruments TMS320C6x tic6x-*-*
1908 Renesas RL78 rl78-*-elf
1910 *** Changes in GDB 7.3.1
1912 * The build failure for NetBSD and OpenBSD targets have now been fixed.
1914 *** Changes in GDB 7.3
1916 * GDB has a new command: "thread find [REGEXP]".
1917 It finds the thread id whose name, target id, or thread extra info
1918 matches the given regular expression.
1920 * The "catch syscall" command now works on mips*-linux* targets.
1922 * The -data-disassemble MI command now supports modes 2 and 3 for
1923 dumping the instruction opcodes.
1925 * New command line options
1927 -data-directory DIR Specify DIR as the "data-directory".
1928 This is mostly for testing purposes.
1930 * The "maint set python auto-load on|off" command has been renamed to
1931 "set auto-load-scripts on|off".
1933 * GDB has a new command: "set directories".
1934 It is like the "dir" command except that it replaces the
1935 source path list instead of augmenting it.
1937 * GDB now understands thread names.
1939 On GNU/Linux, "info threads" will display the thread name as set by
1940 prctl or pthread_setname_np.
1942 There is also a new command, "thread name", which can be used to
1943 assign a name internally for GDB to display.
1946 Initial support for the OpenCL C language (http://www.khronos.org/opencl)
1947 has been integrated into GDB.
1951 ** The function gdb.Write now accepts an optional keyword 'stream'.
1952 This keyword, when provided, will direct the output to either
1953 stdout, stderr, or GDB's logging output.
1955 ** Parameters can now be be sub-classed in Python, and in particular
1956 you may implement the get_set_doc and get_show_doc functions.
1957 This improves how Parameter set/show documentation is processed
1958 and allows for more dynamic content.
1960 ** Symbols, Symbol Table, Symbol Table and Line, Object Files,
1961 Inferior, Inferior Thread, Blocks, and Block Iterator APIs now
1962 have an is_valid method.
1964 ** Breakpoints can now be sub-classed in Python, and in particular
1965 you may implement a 'stop' function that is executed each time
1966 the inferior reaches that breakpoint.
1968 ** New function gdb.lookup_global_symbol looks up a global symbol.
1970 ** GDB values in Python are now callable if the value represents a
1971 function. For example, if 'some_value' represents a function that
1972 takes two integer parameters and returns a value, you can call
1973 that function like so:
1975 result = some_value (10,20)
1977 ** Module gdb.types has been added.
1978 It contains a collection of utilities for working with gdb.Types objects:
1979 get_basic_type, has_field, make_enum_dict.
1981 ** Module gdb.printing has been added.
1982 It contains utilities for writing and registering pretty-printers.
1983 New classes: PrettyPrinter, SubPrettyPrinter,
1984 RegexpCollectionPrettyPrinter.
1985 New function: register_pretty_printer.
1987 ** New commands "info pretty-printers", "enable pretty-printer" and
1988 "disable pretty-printer" have been added.
1990 ** gdb.parameter("directories") is now available.
1992 ** New function gdb.newest_frame returns the newest frame in the
1995 ** The gdb.InferiorThread class has a new "name" attribute. This
1996 holds the thread's name.
1998 ** Python Support for Inferior events.
1999 Python scripts can add observers to be notified of events
2000 occurring in the process being debugged.
2001 The following events are currently supported:
2002 - gdb.events.cont Continue event.
2003 - gdb.events.exited Inferior exited event.
2004 - gdb.events.stop Signal received, and Breakpoint hit events.
2008 ** GDB now puts template parameters in scope when debugging in an
2009 instantiation. For example, if you have:
2011 template<int X> int func (void) { return X; }
2013 then if you step into func<5>, "print X" will show "5". This
2014 feature requires proper debuginfo support from the compiler; it
2015 was added to GCC 4.5.
2017 ** The motion commands "next", "finish", "until", and "advance" now
2018 work better when exceptions are thrown. In particular, GDB will
2019 no longer lose control of the inferior; instead, the GDB will
2020 stop the inferior at the point at which the exception is caught.
2021 This functionality requires a change in the exception handling
2022 code that was introduced in GCC 4.5.
2024 * GDB now follows GCC's rules on accessing volatile objects when
2025 reading or writing target state during expression evaluation.
2026 One notable difference to prior behavior is that "print x = 0"
2027 no longer generates a read of x; the value of the assignment is
2028 now always taken directly from the value being assigned.
2030 * GDB now has some support for using labels in the program's source in
2031 linespecs. For instance, you can use "advance label" to continue
2032 execution to a label.
2034 * GDB now has support for reading and writing a new .gdb_index
2035 section. This section holds a fast index of DWARF debugging
2036 information and can be used to greatly speed up GDB startup and
2037 operation. See the documentation for `save gdb-index' for details.
2039 * The "watch" command now accepts an optional "-location" argument.
2040 When used, this causes GDB to watch the memory referred to by the
2041 expression. Such a watchpoint is never deleted due to it going out
2044 * GDB now supports thread debugging of core dumps on GNU/Linux.
2046 GDB now activates thread debugging using the libthread_db library
2047 when debugging GNU/Linux core dumps, similarly to when debugging
2048 live processes. As a result, when debugging a core dump file, GDB
2049 is now able to display pthread_t ids of threads. For example, "info
2050 threads" shows the same output as when debugging the process when it
2051 was live. In earlier releases, you'd see something like this:
2054 * 1 LWP 6780 main () at main.c:10
2056 While now you see this:
2059 * 1 Thread 0x7f0f5712a700 (LWP 6780) main () at main.c:10
2061 It is also now possible to inspect TLS variables when debugging core
2064 When debugging a core dump generated on a machine other than the one
2065 used to run GDB, you may need to point GDB at the correct
2066 libthread_db library with the "set libthread-db-search-path"
2067 command. See the user manual for more details on this command.
2069 * When natively debugging programs on PowerPC BookE processors running
2070 a Linux kernel version 2.6.34 or later, GDB supports ranged breakpoints,
2071 which stop execution of the inferior whenever it executes an instruction
2072 at any address within the specified range. See the "PowerPC Embedded"
2073 section in the user manual for more details.
2075 * New features in the GDB remote stub, GDBserver
2077 ** GDBserver is now supported on PowerPC LynxOS (versions 4.x and 5.x),
2078 and i686 LynxOS (version 5.x).
2080 ** GDBserver is now supported on Blackfin Linux.
2082 * New native configurations
2084 ia64 HP-UX ia64-*-hpux*
2088 Analog Devices, Inc. Blackfin Processor bfin-*
2090 * Ada task switching is now supported on sparc-elf targets when
2091 debugging a program using the Ravenscar Profile. For more information,
2092 see the "Tasking Support when using the Ravenscar Profile" section
2093 in the GDB user manual.
2095 * Guile support was removed.
2097 * New features in the GNU simulator
2099 ** The --map-info flag lists all known core mappings.
2101 ** CFI flashes may be simulated via the "cfi" device.
2103 *** Changes in GDB 7.2
2105 * Shared library support for remote targets by default
2107 When GDB is configured for a generic, non-OS specific target, like
2108 for example, --target=arm-eabi or one of the many *-*-elf targets,
2109 GDB now queries remote stubs for loaded shared libraries using the
2110 `qXfer:libraries:read' packet. Previously, shared library support
2111 was always disabled for such configurations.
2115 ** Argument Dependent Lookup (ADL)
2117 In C++ ADL lookup directs function search to the namespaces of its
2118 arguments even if the namespace has not been imported.
2128 Here the compiler will search for `foo' in the namespace of 'b'
2129 and find A::foo. GDB now supports this. This construct is commonly
2130 used in the Standard Template Library for operators.
2132 ** Improved User Defined Operator Support
2134 In addition to member operators, GDB now supports lookup of operators
2135 defined in a namespace and imported with a `using' directive, operators
2136 defined in the global scope, operators imported implicitly from an
2137 anonymous namespace, and the ADL operators mentioned in the previous
2139 GDB now also supports proper overload resolution for all the previously
2140 mentioned flavors of operators.
2142 ** static const class members
2144 Printing of static const class members that are initialized in the
2145 class definition has been fixed.
2147 * Windows Thread Information Block access.
2149 On Windows targets, GDB now supports displaying the Windows Thread
2150 Information Block (TIB) structure. This structure is visible either
2151 by using the new command `info w32 thread-information-block' or, by
2152 dereferencing the new convenience variable named `$_tlb', a
2153 thread-specific pointer to the TIB. This feature is also supported
2154 when remote debugging using GDBserver.
2156 * Static tracepoints
2158 Static tracepoints are calls in the user program into a tracing
2159 library. One such library is a port of the LTTng kernel tracer to
2160 userspace --- UST (LTTng Userspace Tracer, http://lttng.org/ust).
2161 When debugging with GDBserver, GDB now supports combining the GDB
2162 tracepoint machinery with such libraries. For example: the user can
2163 use GDB to probe a static tracepoint marker (a call from the user
2164 program into the tracing library) with the new "strace" command (see
2165 "New commands" below). This creates a "static tracepoint" in the
2166 breakpoint list, that can be manipulated with the same feature set
2167 as fast and regular tracepoints. E.g., collect registers, local and
2168 global variables, collect trace state variables, and define
2169 tracepoint conditions. In addition, the user can collect extra
2170 static tracepoint marker specific data, by collecting the new
2171 $_sdata internal variable. When analyzing the trace buffer, you can
2172 inspect $_sdata like any other variable available to GDB. For more
2173 information, see the "Tracepoints" chapter in GDB user manual. New
2174 remote packets have been defined to support static tracepoints, see
2175 the "New remote packets" section below.
2177 * Better reconstruction of tracepoints after disconnected tracing
2179 GDB will attempt to download the original source form of tracepoint
2180 definitions when starting a trace run, and then will upload these
2181 upon reconnection to the target, resulting in a more accurate
2182 reconstruction of the tracepoints that are in use on the target.
2186 You can now exercise direct control over the ways that GDB can
2187 affect your program. For instance, you can disallow the setting of
2188 breakpoints, so that the program can run continuously (assuming
2189 non-stop mode). In addition, the "observer" variable is available
2190 to switch all of the different controls; in observer mode, GDB
2191 cannot affect the target's behavior at all, which is useful for
2192 tasks like diagnosing live systems in the field.
2194 * The new convenience variable $_thread holds the number of the
2197 * New remote packets
2201 Return the address of the Windows Thread Information Block of a given thread.
2205 In response to several of the tracepoint packets, the target may now
2206 also respond with a number of intermediate `qRelocInsn' request
2207 packets before the final result packet, to have GDB handle
2208 relocating an instruction to execute at a different address. This
2209 is particularly useful for stubs that support fast tracepoints. GDB
2210 reports support for this feature in the qSupported packet.
2214 List static tracepoint markers in the target program.
2218 List static tracepoint markers at a given address in the target
2221 qXfer:statictrace:read
2223 Read the static trace data collected (by a `collect $_sdata'
2224 tracepoint action). The remote stub reports support for this packet
2225 to gdb's qSupported query.
2229 Send the current settings of GDB's permission flags.
2233 Send part of the source (textual) form of a tracepoint definition,
2234 which includes location, conditional, and action list.
2236 * The source command now accepts a -s option to force searching for the
2237 script in the source search path even if the script name specifies
2240 * New features in the GDB remote stub, GDBserver
2242 - GDBserver now support tracepoints (including fast tracepoints, and
2243 static tracepoints). The feature is currently supported by the
2244 i386-linux and amd64-linux builds. See the "Tracepoints support
2245 in gdbserver" section in the manual for more information.
2247 GDBserver JIT compiles the tracepoint's conditional agent
2248 expression bytecode into native code whenever possible for low
2249 overhead dynamic tracepoints conditionals. For such tracepoints,
2250 an expression that examines program state is evaluated when the
2251 tracepoint is reached, in order to determine whether to capture
2252 trace data. If the condition is simple and false, processing the
2253 tracepoint finishes very quickly and no data is gathered.
2255 GDBserver interfaces with the UST (LTTng Userspace Tracer) library
2256 for static tracepoints support.
2258 - GDBserver now supports x86_64 Windows 64-bit debugging.
2260 * GDB now sends xmlRegisters= in qSupported packet to indicate that
2261 it understands register description.
2263 * The --batch flag now disables pagination and queries.
2265 * X86 general purpose registers
2267 GDB now supports reading/writing byte, word and double-word x86
2268 general purpose registers directly. This means you can use, say,
2269 $ah or $ax to refer, respectively, to the byte register AH and
2270 16-bit word register AX that are actually portions of the 32-bit
2271 register EAX or 64-bit register RAX.
2273 * The `commands' command now accepts a range of breakpoints to modify.
2274 A plain `commands' following a command that creates multiple
2275 breakpoints affects all the breakpoints set by that command. This
2276 applies to breakpoints set by `rbreak', and also applies when a
2277 single `break' command creates multiple breakpoints (e.g.,
2278 breakpoints on overloaded c++ functions).
2280 * The `rbreak' command now accepts a filename specification as part of
2281 its argument, limiting the functions selected by the regex to those
2282 in the specified file.
2284 * Support for remote debugging Windows and SymbianOS shared libraries
2285 from Unix hosts has been improved. Non Windows GDB builds now can
2286 understand target reported file names that follow MS-DOS based file
2287 system semantics, such as file names that include drive letters and
2288 use the backslash character as directory separator. This makes it
2289 possible to transparently use the "set sysroot" and "set
2290 solib-search-path" on Unix hosts to point as host copies of the
2291 target's shared libraries. See the new command "set
2292 target-file-system-kind" described below, and the "Commands to
2293 specify files" section in the user manual for more information.
2297 eval template, expressions...
2298 Convert the values of one or more expressions under the control
2299 of the string template to a command line, and call it.
2301 set target-file-system-kind unix|dos-based|auto
2302 show target-file-system-kind
2303 Set or show the assumed file system kind for target reported file
2306 save breakpoints <filename>
2307 Save all current breakpoint definitions to a file suitable for use
2308 in a later debugging session. To read the saved breakpoint
2309 definitions, use the `source' command.
2311 `save tracepoints' is a new alias for `save-tracepoints'. The latter
2314 info static-tracepoint-markers
2315 Display information about static tracepoint markers in the target.
2317 strace FN | FILE:LINE | *ADDR | -m MARKER_ID
2318 Define a static tracepoint by probing a marker at the given
2319 function, line, address, or marker ID.
2323 Enable and disable observer mode.
2325 set may-write-registers on|off
2326 set may-write-memory on|off
2327 set may-insert-breakpoints on|off
2328 set may-insert-tracepoints on|off
2329 set may-insert-fast-tracepoints on|off
2330 set may-interrupt on|off
2331 Set individual permissions for GDB effects on the target. Note that
2332 some of these settings can have undesirable or surprising
2333 consequences, particularly when changed in the middle of a session.
2334 For instance, disabling the writing of memory can prevent
2335 breakpoints from being inserted, cause single-stepping to fail, or
2336 even crash your program, if you disable after breakpoints have been
2337 inserted. However, GDB should not crash.
2339 set record memory-query on|off
2340 show record memory-query
2341 Control whether to stop the inferior if memory changes caused
2342 by an instruction cannot be recorded.
2347 The disassemble command now supports "start,+length" form of two arguments.
2351 ** GDB now provides a new directory location, called the python directory,
2352 where Python scripts written for GDB can be installed. The location
2353 of that directory is <data-directory>/python, where <data-directory>
2354 is the GDB data directory. For more details, see section `Scripting
2355 GDB using Python' in the manual.
2357 ** The GDB Python API now has access to breakpoints, symbols, symbol
2358 tables, program spaces, inferiors, threads and frame's code blocks.
2359 Additionally, GDB Parameters can now be created from the API, and
2360 manipulated via set/show in the CLI.
2362 ** New functions gdb.target_charset, gdb.target_wide_charset,
2363 gdb.progspaces, gdb.current_progspace, and gdb.string_to_argv.
2365 ** New exception gdb.GdbError.
2367 ** Pretty-printers are now also looked up in the current program space.
2369 ** Pretty-printers can now be individually enabled and disabled.
2371 ** GDB now looks for names of Python scripts to auto-load in a
2372 special section named `.debug_gdb_scripts', in addition to looking
2373 for a OBJFILE-gdb.py script when OBJFILE is read by the debugger.
2375 * Tracepoint actions were unified with breakpoint commands. In particular,
2376 there are no longer differences in "info break" output for breakpoints and
2377 tracepoints and the "commands" command can be used for both tracepoints and
2378 regular breakpoints.
2382 ARM Symbian arm*-*-symbianelf*
2384 * D language support.
2385 GDB now supports debugging programs written in the D programming
2388 * GDB now supports the extended ptrace interface for PowerPC which is
2389 available since Linux kernel version 2.6.34. This automatically enables
2390 any hardware breakpoints and additional hardware watchpoints available in
2391 the processor. The old ptrace interface exposes just one hardware
2392 watchpoint and no hardware breakpoints.
2394 * GDB is now able to use the Data Value Compare (DVC) register available on
2395 embedded PowerPC processors to implement in hardware simple watchpoint
2396 conditions of the form:
2398 watch ADDRESS|VARIABLE if ADDRESS|VARIABLE == CONSTANT EXPRESSION
2400 This works in native GDB running on Linux kernels with the extended ptrace
2401 interface mentioned above.
2403 *** Changes in GDB 7.1
2407 ** Namespace Support
2409 GDB now supports importing of namespaces in C++. This enables the
2410 user to inspect variables from imported namespaces. Support for
2411 namepace aliasing has also been added. So, if a namespace is
2412 aliased in the current scope (e.g. namepace C=A; ) the user can
2413 print variables using the alias (e.g. (gdb) print C::x).
2417 All known bugs relating to the printing of virtual base class were
2418 fixed. It is now possible to call overloaded static methods using a
2423 The C++ cast operators static_cast<>, dynamic_cast<>, const_cast<>,
2424 and reinterpret_cast<> are now handled by the C++ expression parser.
2428 Xilinx MicroBlaze microblaze-*-*
2433 Xilinx MicroBlaze microblaze
2436 * Multi-program debugging.
2438 GDB now has support for multi-program (a.k.a. multi-executable or
2439 multi-exec) debugging. This allows for debugging multiple inferiors
2440 simultaneously each running a different program under the same GDB
2441 session. See "Debugging Multiple Inferiors and Programs" in the
2442 manual for more information. This implied some user visible changes
2443 in the multi-inferior support. For example, "info inferiors" now
2444 lists inferiors that are not running yet or that have exited
2445 already. See also "New commands" and "New options" below.
2447 * New tracing features
2449 GDB's tracepoint facility now includes several new features:
2451 ** Trace state variables
2453 GDB tracepoints now include support for trace state variables, which
2454 are variables managed by the target agent during a tracing
2455 experiment. They are useful for tracepoints that trigger each
2456 other, so for instance one tracepoint can count hits in a variable,
2457 and then a second tracepoint has a condition that is true when the
2458 count reaches a particular value. Trace state variables share the
2459 $-syntax of GDB convenience variables, and can appear in both
2460 tracepoint actions and condition expressions. Use the "tvariable"
2461 command to create, and "info tvariables" to view; see "Trace State
2462 Variables" in the manual for more detail.
2466 GDB now includes an option for defining fast tracepoints, which
2467 targets may implement more efficiently, such as by installing a jump
2468 into the target agent rather than a trap instruction. The resulting
2469 speedup can be by two orders of magnitude or more, although the
2470 tradeoff is that some program locations on some target architectures
2471 might not allow fast tracepoint installation, for instance if the
2472 instruction to be replaced is shorter than the jump. To request a
2473 fast tracepoint, use the "ftrace" command, with syntax identical to
2474 the regular trace command.
2476 ** Disconnected tracing
2478 It is now possible to detach GDB from the target while it is running
2479 a trace experiment, then reconnect later to see how the experiment
2480 is going. In addition, a new variable disconnected-tracing lets you
2481 tell the target agent whether to continue running a trace if the
2482 connection is lost unexpectedly.
2486 GDB now has the ability to save the trace buffer into a file, and
2487 then use that file as a target, similarly to you can do with
2488 corefiles. You can select trace frames, print data that was
2489 collected in them, and use tstatus to display the state of the
2490 tracing run at the moment that it was saved. To create a trace
2491 file, use "tsave <filename>", and to use it, do "target tfile
2494 ** Circular trace buffer
2496 You can ask the target agent to handle the trace buffer as a
2497 circular buffer, discarding the oldest trace frames to make room for
2498 newer ones, by setting circular-trace-buffer to on. This feature may
2499 not be available for all target agents.
2504 The disassemble command, when invoked with two arguments, now requires
2505 the arguments to be comma-separated.
2508 The info variables command now displays variable definitions. Files
2509 which only declare a variable are not shown.
2512 The source command is now capable of sourcing Python scripts.
2513 This feature is dependent on the debugger being build with Python
2516 Related to this enhancement is also the introduction of a new command
2517 "set script-extension" (see below).
2519 * New commands (for set/show, see "New options" below)
2521 record save [<FILENAME>]
2522 Save a file (in core file format) containing the process record
2523 execution log for replay debugging at a later time.
2525 record restore <FILENAME>
2526 Restore the process record execution log that was saved at an
2527 earlier time, for replay debugging.
2529 add-inferior [-copies <N>] [-exec <FILENAME>]
2532 clone-inferior [-copies <N>] [ID]
2533 Make a new inferior ready to execute the same program another
2534 inferior has loaded.
2539 maint info program-spaces
2540 List the program spaces loaded into GDB.
2542 set remote interrupt-sequence [Ctrl-C | BREAK | BREAK-g]
2543 show remote interrupt-sequence
2544 Allow the user to select one of ^C, a BREAK signal or BREAK-g
2545 as the sequence to the remote target in order to interrupt the execution.
2546 Ctrl-C is a default. Some system prefers BREAK which is high level of
2547 serial line for some certain time. Linux kernel prefers BREAK-g, a.k.a
2548 Magic SysRq g. It is BREAK signal and character 'g'.
2550 set remote interrupt-on-connect [on | off]
2551 show remote interrupt-on-connect
2552 When interrupt-on-connect is ON, gdb sends interrupt-sequence to
2553 remote target when gdb connects to it. This is needed when you debug
2556 set remotebreak [on | off]
2558 Deprecated. Use "set/show remote interrupt-sequence" instead.
2560 tvariable $NAME [ = EXP ]
2561 Create or modify a trace state variable.
2564 List trace state variables and their values.
2566 delete tvariable $NAME ...
2567 Delete one or more trace state variables.
2570 Evaluate the given expressions without collecting anything into the
2571 trace buffer. (Valid in tracepoint actions only.)
2573 ftrace FN / FILE:LINE / *ADDR
2574 Define a fast tracepoint at the given function, line, or address.
2576 * New expression syntax
2578 GDB now parses the 0b prefix of binary numbers the same way as GCC does.
2579 GDB now parses 0b101010 identically with 42.
2583 set follow-exec-mode new|same
2584 show follow-exec-mode
2585 Control whether GDB reuses the same inferior across an exec call or
2586 creates a new one. This is useful to be able to restart the old
2587 executable after the inferior having done an exec call.
2589 set default-collect EXPR, ...
2590 show default-collect
2591 Define a list of expressions to be collected at each tracepoint.
2592 This is a useful way to ensure essential items are not overlooked,
2593 such as registers or a critical global variable.
2595 set disconnected-tracing
2596 show disconnected-tracing
2597 If set to 1, the target is instructed to continue tracing if it
2598 loses its connection to GDB. If 0, the target is to stop tracing
2601 set circular-trace-buffer
2602 show circular-trace-buffer
2603 If set to on, the target is instructed to use a circular trace buffer
2604 and discard the oldest trace frames instead of stopping the trace due
2605 to a full trace buffer. If set to off, the trace stops when the buffer
2606 fills up. Some targets may not support this.
2608 set script-extension off|soft|strict
2609 show script-extension
2610 If set to "off", the debugger does not perform any script language
2611 recognition, and all sourced files are assumed to be GDB scripts.
2612 If set to "soft" (the default), files are sourced according to
2613 filename extension, falling back to GDB scripts if the first
2615 If set to "strict", files are sourced according to filename extension.
2617 set ada trust-PAD-over-XVS on|off
2618 show ada trust-PAD-over-XVS
2619 If off, activate a workaround against a bug in the debugging information
2620 generated by the compiler for PAD types (see gcc/exp_dbug.ads in
2621 the GCC sources for more information about the GNAT encoding and
2622 PAD types in particular). It is always safe to set this option to
2623 off, but this introduces a slight performance penalty. The default
2626 * Python API Improvements
2628 ** GDB provides the new class gdb.LazyString. This is useful in
2629 some pretty-printing cases. The new method gdb.Value.lazy_string
2630 provides a simple way to create objects of this type.
2632 ** The fields returned by gdb.Type.fields now have an
2633 `is_base_class' attribute.
2635 ** The new method gdb.Type.range returns the range of an array type.
2637 ** The new method gdb.parse_and_eval can be used to parse and
2638 evaluate an expression.
2640 * New remote packets
2643 Define a trace state variable.
2646 Get the current value of a trace state variable.
2649 Set desired tracing behavior upon disconnection.
2652 Set the trace buffer to be linear or circular.
2655 Get data about the tracepoints currently in use.
2659 Process record now works correctly with hardware watchpoints.
2661 Multiple bug fixes have been made to the mips-irix port, making it
2662 much more reliable. In particular:
2663 - Debugging threaded applications is now possible again. Previously,
2664 GDB would hang while starting the program, or while waiting for
2665 the program to stop at a breakpoint.
2666 - Attaching to a running process no longer hangs.
2667 - An error occurring while loading a core file has been fixed.
2668 - Changing the value of the PC register now works again. This fixes
2669 problems observed when using the "jump" command, or when calling
2670 a function from GDB, or even when assigning a new value to $pc.
2671 - With the "finish" and "return" commands, the return value for functions
2672 returning a small array is now correctly printed.
2673 - It is now possible to break on shared library code which gets executed
2674 during a shared library init phase (code executed while executing
2675 their .init section). Previously, the breakpoint would have no effect.
2676 - GDB is now able to backtrace through the signal handler for
2677 non-threaded programs.
2679 PIE (Position Independent Executable) programs debugging is now supported.
2680 This includes debugging execution of PIC (Position Independent Code) shared
2681 libraries although for that, it should be possible to run such libraries as an
2684 *** Changes in GDB 7.0
2686 * GDB now has an interface for JIT compilation. Applications that
2687 dynamically generate code can create symbol files in memory and register
2688 them with GDB. For users, the feature should work transparently, and
2689 for JIT developers, the interface is documented in the GDB manual in the
2690 "JIT Compilation Interface" chapter.
2692 * Tracepoints may now be conditional. The syntax is as for
2693 breakpoints; either an "if" clause appended to the "trace" command,
2694 or the "condition" command is available. GDB sends the condition to
2695 the target for evaluation using the same bytecode format as is used
2696 for tracepoint actions.
2698 * The disassemble command now supports: an optional /r modifier, print the
2699 raw instructions in hex as well as in symbolic form, and an optional /m
2700 modifier to print mixed source+assembly.
2702 * Process record and replay
2704 In a architecture environment that supports ``process record and
2705 replay'', ``process record and replay'' target can record a log of
2706 the process execution, and replay it with both forward and reverse
2709 * Reverse debugging: GDB now has new commands reverse-continue, reverse-
2710 step, reverse-next, reverse-finish, reverse-stepi, reverse-nexti, and
2711 set execution-direction {forward|reverse}, for targets that support
2714 * GDB now supports hardware watchpoints on MIPS/Linux systems. This
2715 feature is available with a native GDB running on kernel version
2718 * GDB now has support for multi-byte and wide character sets on the
2719 target. Strings whose character type is wchar_t, char16_t, or
2720 char32_t are now correctly printed. GDB supports wide- and unicode-
2721 literals in C, that is, L'x', L"string", u'x', u"string", U'x', and
2722 U"string" syntax. And, GDB allows the "%ls" and "%lc" formats in
2723 `printf'. This feature requires iconv to work properly; if your
2724 system does not have a working iconv, GDB can use GNU libiconv. See
2725 the installation instructions for more information.
2727 * GDB now supports automatic retrieval of shared library files from
2728 remote targets. To use this feature, specify a system root that begins
2729 with the `remote:' prefix, either via the `set sysroot' command or via
2730 the `--with-sysroot' configure-time option.
2732 * "info sharedlibrary" now takes an optional regex of libraries to show,
2733 and it now reports if a shared library has no debugging information.
2735 * Commands `set debug-file-directory', `set solib-search-path' and `set args'
2736 now complete on file names.
2738 * When completing in expressions, gdb will attempt to limit
2739 completions to allowable structure or union fields, where appropriate.
2740 For instance, consider:
2742 # struct example { int f1; double f2; };
2743 # struct example variable;
2746 If the user types TAB at the end of this command line, the available
2747 completions will be "f1" and "f2".
2749 * Inlined functions are now supported. They show up in backtraces, and
2750 the "step", "next", and "finish" commands handle them automatically.
2752 * GDB now supports the token-splicing (##) and stringification (#)
2753 operators when expanding macros. It also supports variable-arity
2756 * GDB now supports inspecting extra signal information, exported by
2757 the new $_siginfo convenience variable. The feature is currently
2758 implemented on linux ARM, i386 and amd64.
2760 * GDB can now display the VFP floating point registers and NEON vector
2761 registers on ARM targets. Both ARM GNU/Linux native GDB and gdbserver
2762 can provide these registers (requires Linux 2.6.30 or later). Remote
2763 and simulator targets may also provide them.
2765 * New remote packets
2768 Search memory for a sequence of bytes.
2771 Turn off `+'/`-' protocol acknowledgments to permit more efficient
2772 operation over reliable transport links. Use of this packet is
2773 controlled by the `set remote noack-packet' command.
2776 Kill the process with the specified process ID. Use this in preference
2777 to `k' when multiprocess protocol extensions are supported.
2780 Obtains additional operating system information
2784 Read or write additional signal information.
2786 * Removed remote protocol undocumented extension
2788 An undocumented extension to the remote protocol's `S' stop reply
2789 packet that permited the stub to pass a process id was removed.
2790 Remote servers should use the `T' stop reply packet instead.
2792 * GDB now supports multiple function calling conventions according to the
2793 DWARF-2 DW_AT_calling_convention function attribute.
2795 * The SH target utilizes the aforementioned change to distinguish between gcc
2796 and Renesas calling convention. It also adds the new CLI commands
2797 `set/show sh calling-convention'.
2799 * GDB can now read compressed debug sections, as produced by GNU gold
2800 with the --compress-debug-sections=zlib flag.
2802 * 64-bit core files are now supported on AIX.
2804 * Thread switching is now supported on Tru64.
2806 * Watchpoints can now be set on unreadable memory locations, e.g. addresses
2807 which will be allocated using malloc later in program execution.
2809 * The qXfer:libraries:read remote procotol packet now allows passing a
2810 list of section offsets.
2812 * On GNU/Linux, GDB can now attach to stopped processes. Several race
2813 conditions handling signals delivered during attach or thread creation
2814 have also been fixed.
2816 * GDB now supports the use of DWARF boolean types for Ada's type Boolean.
2817 From the user's standpoint, all unqualified instances of True and False
2818 are treated as the standard definitions, regardless of context.
2820 * GDB now parses C++ symbol and type names more flexibly. For
2823 template<typename T> class C { };
2826 GDB will now correctly handle all of:
2828 ptype C<char const *>
2829 ptype C<char const*>
2830 ptype C<const char *>
2831 ptype C<const char*>
2833 * New features in the GDB remote stub, gdbserver
2835 - The "--wrapper" command-line argument tells gdbserver to use a
2836 wrapper program to launch programs for debugging.
2838 - On PowerPC and S/390 targets, it is now possible to use a single
2839 gdbserver executable to debug both 32-bit and 64-bit programs.
2840 (This requires gdbserver itself to be built as a 64-bit executable.)
2842 - gdbserver uses the new noack protocol mode for TCP connections to
2843 reduce communications latency, if also supported and enabled in GDB.
2845 - Support for the sparc64-linux-gnu target is now included in
2848 - The amd64-linux build of gdbserver now supports debugging both
2849 32-bit and 64-bit programs.
2851 - The i386-linux, amd64-linux, and i386-win32 builds of gdbserver
2852 now support hardware watchpoints, and will use them automatically
2857 GDB now has support for scripting using Python. Whether this is
2858 available is determined at configure time.
2860 New GDB commands can now be written in Python.
2862 * Ada tasking support
2864 Ada tasks can now be inspected in GDB. The following commands have
2868 Print the list of Ada tasks.
2870 Print detailed information about task number N.
2872 Print the task number of the current task.
2874 Switch the context of debugging to task number N.
2876 * Support for user-defined prefixed commands. The "define" command can
2877 add new commands to existing prefixes, e.g. "target".
2879 * Multi-inferior, multi-process debugging.
2881 GDB now has generalized support for multi-inferior debugging. See
2882 "Debugging Multiple Inferiors" in the manual for more information.
2883 Although availability still depends on target support, the command
2884 set is more uniform now. The GNU/Linux specific multi-forks support
2885 has been migrated to this new framework. This implied some user
2886 visible changes; see "New commands" and also "Removed commands"
2889 * Target descriptions can now describe the target OS ABI. See the
2890 "Target Description Format" section in the user manual for more
2893 * Target descriptions can now describe "compatible" architectures
2894 to indicate that the target can execute applications for a different
2895 architecture in addition to those for the main target architecture.
2896 See the "Target Description Format" section in the user manual for
2899 * Multi-architecture debugging.
2901 GDB now includes general supports for debugging applications on
2902 hybrid systems that use more than one single processor architecture
2903 at the same time. Each such hybrid architecture still requires
2904 specific support to be added. The only hybrid architecture supported
2905 in this version of GDB is the Cell Broadband Engine.
2907 * GDB now supports integrated debugging of Cell/B.E. applications that
2908 use both the PPU and SPU architectures. To enable support for hybrid
2909 Cell/B.E. debugging, you need to configure GDB to support both the
2910 powerpc-linux or powerpc64-linux and the spu-elf targets, using the
2911 --enable-targets configure option.
2913 * Non-stop mode debugging.
2915 For some targets, GDB now supports an optional mode of operation in
2916 which you can examine stopped threads while other threads continue
2917 to execute freely. This is referred to as non-stop mode, with the
2918 old mode referred to as all-stop mode. See the "Non-Stop Mode"
2919 section in the user manual for more information.
2921 To be able to support remote non-stop debugging, a remote stub needs
2922 to implement the non-stop mode remote protocol extensions, as
2923 described in the "Remote Non-Stop" section of the user manual. The
2924 GDB remote stub, gdbserver, has been adjusted to support these
2925 extensions on linux targets.
2927 * New commands (for set/show, see "New options" below)
2929 catch syscall [NAME(S) | NUMBER(S)]
2930 Catch system calls. Arguments, which should be names of system
2931 calls or their numbers, mean catch only those syscalls. Without
2932 arguments, every syscall will be caught. When the inferior issues
2933 any of the specified syscalls, GDB will stop and announce the system
2934 call, both when it is called and when its call returns. This
2935 feature is currently available with a native GDB running on the
2936 Linux Kernel, under the following architectures: x86, x86_64,
2937 PowerPC and PowerPC64.
2939 find [/size-char] [/max-count] start-address, end-address|+search-space-size,
2941 Search memory for a sequence of bytes.
2943 maint set python print-stack
2944 maint show python print-stack
2945 Show a stack trace when an error is encountered in a Python script.
2948 Invoke CODE by passing it to the Python interpreter.
2953 These allow macros to be defined, undefined, and listed
2957 Show operating system information about processes.
2960 List the inferiors currently under GDB's control.
2963 Switch focus to inferior number NUM.
2966 Detach from inferior number NUM.
2969 Kill inferior number NUM.
2973 set spu stop-on-load
2974 show spu stop-on-load
2975 Control whether to stop for new SPE threads during Cell/B.E. debugging.
2977 set spu auto-flush-cache
2978 show spu auto-flush-cache
2979 Control whether to automatically flush the software-managed cache
2980 during Cell/B.E. debugging.
2982 set sh calling-convention
2983 show sh calling-convention
2984 Control the calling convention used when calling SH target functions.
2987 show debug timestamp
2988 Control display of timestamps with GDB debugging output.
2990 set disassemble-next-line
2991 show disassemble-next-line
2992 Control display of disassembled source lines or instructions when
2995 set remote noack-packet
2996 show remote noack-packet
2997 Set/show the use of remote protocol QStartNoAckMode packet. See above
2998 under "New remote packets."
3000 set remote query-attached-packet
3001 show remote query-attached-packet
3002 Control use of remote protocol `qAttached' (query-attached) packet.
3004 set remote read-siginfo-object
3005 show remote read-siginfo-object
3006 Control use of remote protocol `qXfer:siginfo:read' (read-siginfo-object)
3009 set remote write-siginfo-object
3010 show remote write-siginfo-object
3011 Control use of remote protocol `qXfer:siginfo:write' (write-siginfo-object)
3014 set remote reverse-continue
3015 show remote reverse-continue
3016 Control use of remote protocol 'bc' (reverse-continue) packet.
3018 set remote reverse-step
3019 show remote reverse-step
3020 Control use of remote protocol 'bs' (reverse-step) packet.
3022 set displaced-stepping
3023 show displaced-stepping
3024 Control displaced stepping mode. Displaced stepping is a way to
3025 single-step over breakpoints without removing them from the debuggee.
3026 Also known as "out-of-line single-stepping".
3029 show debug displaced
3030 Control display of debugging info for displaced stepping.
3032 maint set internal-error
3033 maint show internal-error
3034 Control what GDB does when an internal error is detected.
3036 maint set internal-warning
3037 maint show internal-warning
3038 Control what GDB does when an internal warning is detected.
3043 Use a wrapper program to launch programs for debugging.
3045 set multiple-symbols (all|ask|cancel)
3046 show multiple-symbols
3047 The value of this variable can be changed to adjust the debugger behavior
3048 when an expression or a breakpoint location contains an ambiguous symbol
3049 name (an overloaded function name, for instance).
3051 set breakpoint always-inserted
3052 show breakpoint always-inserted
3053 Keep breakpoints always inserted in the target, as opposed to inserting
3054 them when resuming the target, and removing them when the target stops.
3055 This option can improve debugger performance on slow remote targets.
3057 set arm fallback-mode (arm|thumb|auto)
3058 show arm fallback-mode
3059 set arm force-mode (arm|thumb|auto)
3061 These commands control how ARM GDB determines whether instructions
3062 are ARM or Thumb. The default for both settings is auto, which uses
3063 the current CPSR value for instructions without symbols; previous
3064 versions of GDB behaved as if "set arm fallback-mode arm".
3066 set disable-randomization
3067 show disable-randomization
3068 Standalone programs run with the virtual address space randomization enabled
3069 by default on some platforms. This option keeps the addresses stable across
3070 multiple debugging sessions.
3074 Control whether other threads are stopped or not when some thread hits
3079 Requests that asynchronous execution is enabled in the target, if available.
3080 In this case, it's possible to resume target in the background, and interact
3081 with GDB while the target is running. "show target-async" displays the
3082 current state of asynchronous execution of the target.
3084 set target-wide-charset
3085 show target-wide-charset
3086 The target-wide-charset is the name of the character set that GDB
3087 uses when printing characters whose type is wchar_t.
3089 set tcp auto-retry (on|off)
3091 set tcp connect-timeout
3092 show tcp connect-timeout
3093 These commands allow GDB to retry failed TCP connections to a remote stub
3094 with a specified timeout period; this is useful if the stub is launched
3095 in parallel with GDB but may not be ready to accept connections immediately.
3097 set libthread-db-search-path
3098 show libthread-db-search-path
3099 Control list of directories which GDB will search for appropriate
3102 set schedule-multiple (on|off)
3103 show schedule-multiple
3104 Allow GDB to resume all threads of all processes or only threads of
3105 the current process.
3109 Use more aggressive caching for accesses to the stack. This improves
3110 performance of remote debugging (particularly backtraces) without
3111 affecting correctness.
3113 set interactive-mode (on|off|auto)
3114 show interactive-mode
3115 Control whether GDB runs in interactive mode (on) or not (off).
3116 When in interactive mode, GDB waits for the user to answer all
3117 queries. Otherwise, GDB does not wait and assumes the default
3118 answer. When set to auto (the default), GDB determines which
3119 mode to use based on the stdin settings.
3124 For program forks, this is replaced by the new more generic `info
3125 inferiors' command. To list checkpoints, you can still use the
3126 `info checkpoints' command, which was an alias for the `info forks'
3130 Replaced by the new `inferior' command. To switch between
3131 checkpoints, you can still use the `restart' command, which was an
3132 alias for the `fork' command.
3135 This is removed, since some targets don't have a notion of
3136 processes. To switch between processes, you can still use the
3137 `inferior' command using GDB's own inferior number.
3140 For program forks, this is replaced by the new more generic `kill
3141 inferior' command. To delete a checkpoint, you can still use the
3142 `delete checkpoint' command, which was an alias for the `delete
3146 For program forks, this is replaced by the new more generic `detach
3147 inferior' command. To detach a checkpoint, you can still use the
3148 `detach checkpoint' command, which was an alias for the `detach
3151 * New native configurations
3153 x86/x86_64 Darwin i[34567]86-*-darwin*
3155 x86_64 MinGW x86_64-*-mingw*
3159 Lattice Mico32 lm32-*
3160 x86 DICOS i[34567]86-*-dicos*
3161 x86_64 DICOS x86_64-*-dicos*
3164 * The GDB remote stub, gdbserver, now supports x86 Windows CE
3165 (mingw32ce) debugging.
3171 These commands were actually not implemented on any target.
3173 *** Changes in GDB 6.8
3175 * New native configurations
3177 NetBSD/hppa hppa*-*netbsd*
3178 Xtensa GNU/Linux xtensa*-*-linux*
3182 NetBSD/hppa hppa*-*-netbsd*
3183 Xtensa GNU/Lunux xtensa*-*-linux*
3185 * Change in command line behavior -- corefiles vs. process ids.
3187 When the '-p NUMBER' or '--pid NUMBER' options are used, and
3188 attaching to process NUMBER fails, GDB no longer attempts to open a
3189 core file named NUMBER. Attaching to a program using the -c option
3190 is no longer supported. Instead, use the '-p' or '--pid' options.
3192 * GDB can now be built as a native debugger for debugging Windows x86
3193 (mingw32) Portable Executable (PE) programs.
3195 * Pending breakpoints no longer change their number when their address
3198 * GDB now supports breakpoints with multiple locations,
3199 including breakpoints on C++ constructors, inside C++ templates,
3200 and in inlined functions.
3202 * GDB's ability to debug optimized code has been improved. GDB more
3203 accurately identifies function bodies and lexical blocks that occupy
3204 more than one contiguous range of addresses.
3206 * Target descriptions can now describe registers for PowerPC.
3208 * The GDB remote stub, gdbserver, now supports the AltiVec and SPE
3209 registers on PowerPC targets.
3211 * The GDB remote stub, gdbserver, now supports thread debugging on GNU/Linux
3212 targets even when the libthread_db library is not available.
3214 * The GDB remote stub, gdbserver, now supports the new file transfer
3215 commands (remote put, remote get, and remote delete).
3217 * The GDB remote stub, gdbserver, now supports run and attach in
3218 extended-remote mode.
3220 * hppa*64*-*-hpux11* target broken
3221 The debugger is unable to start a program and fails with the following
3222 error: "Error trying to get information about dynamic linker".
3223 The gdb-6.7 release is also affected.
3225 * GDB now supports the --enable-targets= configure option to allow
3226 building a single GDB executable that supports multiple remote
3227 target architectures.
3229 * GDB now supports debugging C and C++ programs which use the
3230 Decimal Floating Point extension. In addition, the PowerPC target
3231 now has a set of pseudo-registers to inspect decimal float values
3232 stored in two consecutive float registers.
3234 * The -break-insert MI command can optionally create pending
3237 * Improved support for debugging Ada
3238 Many improvements to the Ada language support have been made. These
3240 - Better support for Ada2005 interface types
3241 - Improved handling of arrays and slices in general
3242 - Better support for Taft-amendment types
3243 - The '{type} ADDRESS' expression is now allowed on the left hand-side
3245 - Improved command completion in Ada
3248 * GDB on GNU/Linux and HP/UX can now debug through "exec" of a new
3253 set print frame-arguments (all|scalars|none)
3254 show print frame-arguments
3255 The value of this variable can be changed to control which argument
3256 values should be printed by the debugger when displaying a frame.
3261 Transfer files to and from a remote target, and delete remote files.
3268 Transfer files to and from a remote target, and delete remote files.
3270 * New remote packets
3277 Open, close, read, write, and delete files on the remote system.
3280 Attach to an existing process on the remote system, in extended-remote
3284 Run a new process on the remote system, in extended-remote mode.
3286 *** Changes in GDB 6.7
3288 * Resolved 101 resource leaks, null pointer dereferences, etc. in gdb,
3289 bfd, libiberty and opcodes, as revealed by static analysis donated by
3290 Coverity, Inc. (http://scan.coverity.com).
3292 * When looking up multiply-defined global symbols, GDB will now prefer the
3293 symbol definition in the current shared library if it was built using the
3294 -Bsymbolic linker option.
3296 * When the Text User Interface (TUI) is not configured, GDB will now
3297 recognize the -tui command-line option and print a message that the TUI
3300 * The GDB remote stub, gdbserver, now has lower overhead for high
3301 frequency signals (e.g. SIGALRM) via the QPassSignals packet.
3303 * GDB for MIPS targets now autodetects whether a remote target provides
3304 32-bit or 64-bit register values.
3306 * Support for C++ member pointers has been improved.
3308 * GDB now understands XML target descriptions, which specify the
3309 target's overall architecture. GDB can read a description from
3310 a local file or over the remote serial protocol.
3312 * Vectors of single-byte data use a new integer type which is not
3313 automatically displayed as character or string data.
3315 * The /s format now works with the print command. It displays
3316 arrays of single-byte integers and pointers to single-byte integers
3319 * Target descriptions can now describe target-specific registers,
3320 for architectures which have implemented the support (currently
3321 only ARM, M68K, and MIPS).
3323 * GDB and the GDB remote stub, gdbserver, now support the XScale
3326 * The GDB remote stub, gdbserver, has been updated to support
3327 ARM Windows CE (mingw32ce) debugging, and GDB Windows CE support
3328 has been rewritten to use the standard GDB remote protocol.
3330 * GDB can now step into C++ functions which are called through thunks.
3332 * GDB for the Cell/B.E. SPU now supports overlay debugging.
3334 * The GDB remote protocol "qOffsets" packet can now honor ELF segment
3335 layout. It also supports a TextSeg= and DataSeg= response when only
3336 segment base addresses (rather than offsets) are available.
3338 * The /i format now outputs any trailing branch delay slot instructions
3339 immediately following the last instruction within the count specified.
3341 * The GDB remote protocol "T" stop reply packet now supports a
3342 "library" response. Combined with the new "qXfer:libraries:read"
3343 packet, this response allows GDB to debug shared libraries on targets
3344 where the operating system manages the list of loaded libraries (e.g.
3345 Windows and SymbianOS).
3347 * The GDB remote stub, gdbserver, now supports dynamic link libraries
3348 (DLLs) on Windows and Windows CE targets.
3350 * GDB now supports a faster verification that a .debug file matches its binary
3351 according to its build-id signature, if the signature is present.
3357 Enable or disable hardware flow control (RTS/CTS) on the serial port
3358 when debugging using remote targets.
3360 set mem inaccessible-by-default
3361 show mem inaccessible-by-default
3362 If the target supplies a memory map, for instance via the remote
3363 protocol's "qXfer:memory-map:read" packet, setting this variable
3364 prevents GDB from accessing memory outside the memory map. This
3365 is useful for targets with memory mapped registers or which react
3366 badly to accesses of unmapped address space.
3368 set breakpoint auto-hw
3369 show breakpoint auto-hw
3370 If the target supplies a memory map, for instance via the remote
3371 protocol's "qXfer:memory-map:read" packet, setting this variable
3372 lets GDB use hardware breakpoints automatically for memory regions
3373 where it can not use software breakpoints. This covers both the
3374 "break" command and internal breakpoints used for other commands
3375 including "next" and "finish".
3378 catch exception unhandled
3379 Stop the program execution when Ada exceptions are raised.
3382 Stop the program execution when an Ada assertion failed.
3386 Set an alternate system root for target files. This is a more
3387 general version of "set solib-absolute-prefix", which is now
3388 an alias to "set sysroot".
3391 Provide extended SPU facility status information. This set of
3392 commands is available only when debugging the Cell/B.E. SPU
3395 * New native configurations
3397 OpenBSD/sh sh*-*openbsd*
3400 unset tdesc filename
3402 Use the specified local file as an XML target description, and do
3403 not query the target for its built-in description.
3407 OpenBSD/sh sh*-*-openbsd*
3408 MIPS64 GNU/Linux (gdbserver) mips64-linux-gnu
3409 Toshiba Media Processor mep-elf
3411 * New remote packets
3414 Ignore the specified signals; pass them directly to the debugged program
3415 without stopping other threads or reporting them to GDB.
3417 qXfer:features:read:
3418 Read an XML target description from the target, which describes its
3423 Read or write contents of an spufs file on the target system. These
3424 packets are available only on the Cell/B.E. SPU architecture.
3426 qXfer:libraries:read:
3427 Report the loaded shared libraries. Combined with new "T" packet
3428 response, this packet allows GDB to debug shared libraries on
3429 targets where the operating system manages the list of loaded
3430 libraries (e.g. Windows and SymbianOS).
3434 Support for these obsolete configurations has been removed.
3442 i[34567]86-*-lynxos*
3443 i[34567]86-*-netware*
3444 i[34567]86-*-sco3.2v5*
3445 i[34567]86-*-sco3.2v4*
3447 i[34567]86-*-sysv4.2*
3450 i[34567]86-*-unixware2*
3451 i[34567]86-*-unixware*
3460 * Other removed features
3467 Various m68k-only ROM monitors.
3474 Various Renesas ROM monitors and debugging interfaces for SH and
3479 Support for a Macraigor serial interface to on-chip debugging.
3480 GDB does not directly support the newer parallel or USB
3485 A debug information format. The predecessor to DWARF 2 and
3486 DWARF 3, which are still supported.
3488 Support for the HP aCC compiler on HP-UX/PA-RISC
3490 SOM-encapsulated symbolic debugging information, automatic
3491 invocation of pxdb, and the aCC custom C++ ABI. This does not
3492 affect HP-UX for Itanium or GCC for HP-UX/PA-RISC. Code compiled
3493 with aCC can still be debugged on an assembly level.
3495 MIPS ".pdr" sections
3497 A MIPS-specific format used to describe stack frame layout
3498 in debugging information.
3502 GDB could work with an older version of Guile to debug
3503 the interpreter and Scheme programs running in it.
3505 set mips stack-arg-size
3506 set mips saved-gpreg-size
3508 Use "set mips abi" to control parameter passing for MIPS.
3510 *** Changes in GDB 6.6
3515 Cell Broadband Engine SPU spu-elf
3517 * GDB can now be configured as a cross-debugger targeting native Windows
3518 (mingw32) or Cygwin. It can communicate with a remote debugging stub
3519 running on a Windows system over TCP/IP to debug Windows programs.
3521 * The GDB remote stub, gdbserver, has been updated to support Windows and
3522 Cygwin debugging. Both single-threaded and multi-threaded programs are
3525 * The "set trust-readonly-sections" command works again. This command was
3526 broken in GDB 6.3, 6.4, and 6.5.
3528 * The "load" command now supports writing to flash memory, if the remote
3529 stub provides the required support.
3531 * Support for GNU/Linux Thread Local Storage (TLS, per-thread variables) no
3532 longer requires symbolic debug information (e.g. DWARF-2).
3537 unset substitute-path
3538 show substitute-path
3539 Manage a list of substitution rules that GDB uses to rewrite the name
3540 of the directories where the sources are located. This can be useful
3541 for instance when the sources were moved to a different location
3542 between compilation and debugging.
3546 Print each CLI command as it is executed. Each command is prefixed with
3547 a number of `+' symbols representing the nesting depth.
3548 The source command now has a `-v' option to enable the same feature.
3552 The ARM Demon monitor support (RDP protocol, "target rdp").
3554 Kernel Object Display, an embedded debugging feature which only worked with
3555 an obsolete version of Cisco IOS.
3557 The 'set download-write-size' and 'show download-write-size' commands.
3559 * New remote packets
3562 Tell a stub about GDB client features, and request remote target features.
3563 The first feature implemented is PacketSize, which allows the target to
3564 specify the size of packets it can handle - to minimize the number of
3565 packets required and improve performance when connected to a remote
3569 Fetch an OS auxilliary vector from the remote stub. This packet is a
3570 more efficient replacement for qPart:auxv:read.
3572 qXfer:memory-map:read:
3573 Fetch a memory map from the remote stub, including information about
3574 RAM, ROM, and flash memory devices.
3579 Erase and program a flash memory device.
3581 * Removed remote packets
3584 This packet has been replaced by qXfer:auxv:read. Only GDB 6.4 and 6.5
3585 used it, and only gdbserver implemented it.
3587 *** Changes in GDB 6.5
3591 Renesas M32C/M16C m32c-elf
3593 Morpho Technologies ms1 ms1-elf
3597 init-if-undefined Initialize a convenience variable, but
3598 only if it doesn't already have a value.
3600 The following commands are presently only implemented for native GNU/Linux:
3602 checkpoint Save a snapshot of the program state.
3604 restart <n> Return the program state to a
3605 previously saved state.
3607 info checkpoints List currently saved checkpoints.
3609 delete-checkpoint <n> Delete a previously saved checkpoint.
3611 set|show detach-on-fork Tell gdb whether to detach from a newly
3612 forked process, or to keep debugging it.
3614 info forks List forks of the user program that
3615 are available to be debugged.
3617 fork <n> Switch to debugging one of several
3618 forks of the user program that are
3619 available to be debugged.
3621 delete-fork <n> Delete a fork from the list of forks
3622 that are available to be debugged (and
3623 kill the forked process).
3625 detach-fork <n> Delete a fork from the list of forks
3626 that are available to be debugged (and
3627 allow the process to continue).
3631 Morpho Technologies ms2 ms1-elf
3633 * Improved Windows host support
3635 GDB now builds as a cross debugger hosted on i686-mingw32, including
3636 native console support, and remote communications using either
3637 network sockets or serial ports.
3639 * Improved Modula-2 language support
3641 GDB can now print most types in the Modula-2 syntax. This includes:
3642 basic types, set types, record types, enumerated types, range types,
3643 pointer types and ARRAY types. Procedure var parameters are correctly
3644 printed and hexadecimal addresses and character constants are also
3645 written in the Modula-2 syntax. Best results can be obtained by using
3646 GNU Modula-2 together with the -gdwarf-2 command line option.
3650 The ARM rdi-share module.
3652 The Netware NLM debug server.
3654 *** Changes in GDB 6.4
3656 * New native configurations
3658 OpenBSD/arm arm*-*-openbsd*
3659 OpenBSD/mips64 mips64-*-openbsd*
3663 Morpho Technologies ms1 ms1-elf
3665 * New command line options
3667 --batch-silent As for --batch, but totally silent.
3668 --return-child-result The debugger will exist with the same value
3669 the child (debugged) program exited with.
3670 --eval-command COMMAND, -ex COMMAND
3671 Execute a single GDB CLI command. This may be
3672 specified multiple times and in conjunction
3673 with the --command (-x) option.
3675 * Deprecated commands removed
3677 The following commands, that were deprecated in 2000, have been
3681 set|show arm disassembly-flavor set|show arm disassembler
3682 othernames set arm disassembler
3683 set|show remotedebug set|show debug remote
3684 set|show archdebug set|show debug arch
3685 set|show eventdebug set|show debug event
3688 * New BSD user-level threads support
3690 It is now possible to debug programs using the user-level threads
3691 library on OpenBSD and FreeBSD. Currently supported (target)
3694 FreeBSD/amd64 x86_64-*-freebsd*
3695 FreeBSD/i386 i386-*-freebsd*
3696 OpenBSD/i386 i386-*-openbsd*
3698 Note that the new kernel threads libraries introduced in FreeBSD 5.x
3699 are not yet supported.
3701 * New support for Matsushita MN10300 w/sim added
3702 (Work in progress). mn10300-elf.
3704 * REMOVED configurations and files
3706 VxWorks and the XDR protocol *-*-vxworks
3707 Motorola MCORE mcore-*-*
3708 National Semiconductor NS32000 ns32k-*-*
3710 * New "set print array-indexes" command
3712 After turning this setting "on", GDB prints the index of each element
3713 when displaying arrays. The default is "off" to preserve the previous
3716 * VAX floating point support
3718 GDB now supports the not-quite-ieee VAX F and D floating point formats.
3720 * User-defined command support
3722 In addition to using $arg0..$arg9 for argument passing, it is now possible
3723 to use $argc to determine now many arguments have been passed. See the
3724 section on user-defined commands in the user manual for more information.
3726 *** Changes in GDB 6.3:
3728 * New command line option
3730 GDB now accepts -l followed by a number to set the timeout for remote
3733 * GDB works with GCC -feliminate-dwarf2-dups
3735 GDB now supports a more compact representation of DWARF-2 debug
3736 information using DW_FORM_ref_addr references. These are produced
3737 by GCC with the option -feliminate-dwarf2-dups and also by some
3738 proprietary compilers. With GCC, you must use GCC 3.3.4 or later
3739 to use -feliminate-dwarf2-dups.
3741 * Internationalization
3743 When supported by the host system, GDB will be built with
3744 internationalization (libintl). The task of marking up the sources is
3745 continued, we're looking forward to our first translation.
3749 Initial support for debugging programs compiled with the GNAT
3750 implementation of the Ada programming language has been integrated
3751 into GDB. In this release, support is limited to expression evaluation.
3753 * New native configurations
3755 GNU/Linux/m32r m32r-*-linux-gnu
3759 GDB's remote protocol now includes support for the 'p' packet. This
3760 packet is used to fetch individual registers from a remote inferior.
3762 * END-OF-LIFE registers[] compatibility module
3764 GDB's internal register infrastructure has been completely rewritten.
3765 The new infrastructure making possible the implementation of key new
3766 features including 32x64 (e.g., 64-bit amd64 GDB debugging a 32-bit
3769 GDB 6.3 will be the last release to include the the registers[]
3770 compatibility module that allowed out-of-date configurations to
3771 continue to work. This change directly impacts the following
3781 powerpc bdm protocol
3783 Unless there is activity to revive these configurations, they will be
3784 made OBSOLETE in GDB 6.4, and REMOVED from GDB 6.5.
3786 * OBSOLETE configurations and files
3788 Configurations that have been declared obsolete in this release have
3789 been commented out. Unless there is activity to revive these
3790 configurations, the next release of GDB will have their sources
3791 permanently REMOVED.
3800 *** Changes in GDB 6.2.1:
3802 * MIPS `break main; run' gave an heuristic-fence-post warning
3804 When attempting to run even a simple program, a warning about
3805 heuristic-fence-post being hit would be reported. This problem has
3808 * MIPS IRIX 'long double' crashed GDB
3810 When examining a long double variable, GDB would get a segmentation
3811 fault. The crash has been fixed (but GDB 6.2 cannot correctly examine
3812 IRIX long double values).
3816 A bug in the VAX stack code was causing problems with the "next"
3817 command. This problem has been fixed.
3819 *** Changes in GDB 6.2:
3821 * Fix for ``many threads''
3823 On GNU/Linux systems that use the NPTL threads library, a program
3824 rapidly creating and deleting threads would confuse GDB leading to the
3827 ptrace: No such process.
3828 thread_db_get_info: cannot get thread info: generic error
3830 This problem has been fixed.
3832 * "-async" and "-noasync" options removed.
3834 Support for the broken "-noasync" option has been removed (it caused
3837 * New ``start'' command.
3839 This command runs the program until the begining of the main procedure.
3841 * New BSD Kernel Data Access Library (libkvm) interface
3843 Using ``target kvm'' it is now possible to debug kernel core dumps and
3844 live kernel memory images on various FreeBSD, NetBSD and OpenBSD
3845 platforms. Currently supported (native-only) configurations are:
3847 FreeBSD/amd64 x86_64-*-freebsd*
3848 FreeBSD/i386 i?86-*-freebsd*
3849 NetBSD/i386 i?86-*-netbsd*
3850 NetBSD/m68k m68*-*-netbsd*
3851 NetBSD/sparc sparc-*-netbsd*
3852 OpenBSD/amd64 x86_64-*-openbsd*
3853 OpenBSD/i386 i?86-*-openbsd*
3854 OpenBSD/m68k m68*-openbsd*
3855 OpenBSD/sparc sparc-*-openbsd*
3857 * Signal trampoline code overhauled
3859 Many generic problems with GDB's signal handling code have been fixed.
3860 These include: backtraces through non-contiguous stacks; recognition
3861 of sa_sigaction signal trampolines; backtrace from a NULL pointer
3862 call; backtrace through a signal trampoline; step into and out of
3863 signal handlers; and single-stepping in the signal trampoline.
3865 Please note that kernel bugs are a limiting factor here. These
3866 features have been shown to work on an s390 GNU/Linux system that
3867 include a 2.6.8-rc1 kernel. Ref PR breakpoints/1702.
3869 * Cygwin support for DWARF 2 added.
3871 * New native configurations
3873 GNU/Linux/hppa hppa*-*-linux*
3874 OpenBSD/hppa hppa*-*-openbsd*
3875 OpenBSD/m68k m68*-*-openbsd*
3876 OpenBSD/m88k m88*-*-openbsd*
3877 OpenBSD/powerpc powerpc-*-openbsd*
3878 NetBSD/vax vax-*-netbsd*
3879 OpenBSD/vax vax-*-openbsd*
3881 * END-OF-LIFE frame compatibility module
3883 GDB's internal frame infrastructure has been completely rewritten.
3884 The new infrastructure making it possible to support key new features
3885 including DWARF 2 Call Frame Information. To aid in the task of
3886 migrating old configurations to this new infrastructure, a
3887 compatibility module, that allowed old configurations to continue to
3888 work, was also included.
3890 GDB 6.2 will be the last release to include this frame compatibility
3891 module. This change directly impacts the following configurations:
3901 Unless there is activity to revive these configurations, they will be
3902 made OBSOLETE in GDB 6.3, and REMOVED from GDB 6.4.
3904 * REMOVED configurations and files
3906 Sun 3, running SunOS 3 m68*-*-sunos3*
3907 Sun 3, running SunOS 4 m68*-*-sunos4*
3908 Sun 2, running SunOS 3 m68000-*-sunos3*
3909 Sun 2, running SunOS 4 m68000-*-sunos4*
3910 Motorola 680x0 running LynxOS m68*-*-lynxos*
3911 AT&T 3b1/Unix pc m68*-att-*
3912 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
3913 decstation mips-dec-* mips-little-*
3914 riscos mips-*-riscos* mips-*-sysv*
3915 sonymips mips-sony-*
3916 sysv mips*-*-sysv4* (IRIX 5/6 not included)
3918 *** Changes in GDB 6.1.1:
3920 * TUI (Text-mode User Interface) built-in (also included in GDB 6.1)
3922 The TUI (Text-mode User Interface) is now built as part of a default
3923 GDB configuration. It is enabled by either selecting the TUI with the
3924 command line option "-i=tui" or by running the separate "gdbtui"
3925 program. For more information on the TUI, see the manual "Debugging
3928 * Pending breakpoint support (also included in GDB 6.1)
3930 Support has been added to allow you to specify breakpoints in shared
3931 libraries that have not yet been loaded. If a breakpoint location
3932 cannot be found, and the "breakpoint pending" option is set to auto,
3933 GDB queries you if you wish to make the breakpoint pending on a future
3934 shared-library load. If and when GDB resolves the breakpoint symbol,
3935 the pending breakpoint is removed as one or more regular breakpoints
3938 Pending breakpoints are very useful for GCJ Java debugging.
3940 * Fixed ISO-C build problems
3942 The files bfd/elf-bfd.h, gdb/dictionary.c and gdb/types.c contained
3943 non ISO-C code that stopped them being built using a more strict ISO-C
3944 compiler (e.g., IBM's C compiler).
3946 * Fixed build problem on IRIX 5
3948 Due to header problems with <sys/proc.h>, the file gdb/proc-api.c
3949 wasn't able to compile compile on an IRIX 5 system.
3951 * Added execute permission to gdb/gdbserver/configure
3953 The shell script gdb/testsuite/gdb.stabs/configure lacked execute
3954 permission. This bug would cause configure to fail on a number of
3955 systems (Solaris, IRIX). Ref: server/519.
3957 * Fixed build problem on hpux2.0w-hp-hpux11.00 using the HP ANSI C compiler
3959 Older HPUX ANSI C compilers did not accept variable array sizes. somsolib.c
3960 has been updated to use constant array sizes.
3962 * Fixed a panic in the DWARF Call Frame Info code on Solaris 2.7
3964 GCC 3.3.2, on Solaris 2.7, includes the DW_EH_PE_funcrel encoding in
3965 its generated DWARF Call Frame Info. This encoding was causing GDB to
3966 panic, that panic has been fixed. Ref: gdb/1628.
3968 * Fixed a problem when examining parameters in shared library code.
3970 When examining parameters in optimized shared library code generated
3971 by a mainline GCC, GDB would incorrectly report ``Variable "..." is
3972 not available''. GDB now correctly displays the variable's value.
3974 *** Changes in GDB 6.1:
3976 * Removed --with-mmalloc
3978 Support for the mmalloc memory manager has been removed, as it
3979 conflicted with the internal gdb byte cache.
3981 * Changes in AMD64 configurations
3983 The AMD64 target now includes the %cs and %ss registers. As a result
3984 the AMD64 remote protocol has changed; this affects the floating-point
3985 and SSE registers. If you rely on those registers for your debugging,
3986 you should upgrade gdbserver on the remote side.
3988 * Revised SPARC target
3990 The SPARC target has been completely revised, incorporating the
3991 FreeBSD/sparc64 support that was added for GDB 6.0. As a result
3992 support for LynxOS and SunOS 4 has been dropped. Calling functions
3993 from within GDB on operating systems with a non-executable stack
3994 (Solaris, OpenBSD) now works.
3998 GDB has a new C++ demangler which does a better job on the mangled
3999 names generated by current versions of g++. It also runs faster, so
4000 with this and other changes gdb should now start faster on large C++
4003 * DWARF 2 Location Expressions
4005 GDB support for location expressions has been extended to support function
4006 arguments and frame bases. Older versions of GDB could crash when they
4009 * C++ nested types and namespaces
4011 GDB's support for nested types and namespaces in C++ has been
4012 improved, especially if you use the DWARF 2 debugging format. (This
4013 is the default for recent versions of GCC on most platforms.)
4014 Specifically, if you have a class "Inner" defined within a class or
4015 namespace "Outer", then GDB realizes that the class's name is
4016 "Outer::Inner", not simply "Inner". This should greatly reduce the
4017 frequency of complaints about not finding RTTI symbols. In addition,
4018 if you are stopped at inside of a function defined within a namespace,
4019 GDB modifies its name lookup accordingly.
4021 * New native configurations
4023 NetBSD/amd64 x86_64-*-netbsd*
4024 OpenBSD/amd64 x86_64-*-openbsd*
4025 OpenBSD/alpha alpha*-*-openbsd*
4026 OpenBSD/sparc sparc-*-openbsd*
4027 OpenBSD/sparc64 sparc64-*-openbsd*
4029 * New debugging protocols
4031 M32R with SDI protocol m32r-*-elf*
4033 * "set prompt-escape-char" command deleted.
4035 The command "set prompt-escape-char" has been deleted. This command,
4036 and its very obscure effet on GDB's prompt, was never documented,
4037 tested, nor mentioned in the NEWS file.
4039 * OBSOLETE configurations and files
4041 Configurations that have been declared obsolete in this release have
4042 been commented out. Unless there is activity to revive these
4043 configurations, the next release of GDB will have their sources
4044 permanently REMOVED.
4046 Sun 3, running SunOS 3 m68*-*-sunos3*
4047 Sun 3, running SunOS 4 m68*-*-sunos4*
4048 Sun 2, running SunOS 3 m68000-*-sunos3*
4049 Sun 2, running SunOS 4 m68000-*-sunos4*
4050 Motorola 680x0 running LynxOS m68*-*-lynxos*
4051 AT&T 3b1/Unix pc m68*-att-*
4052 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
4053 decstation mips-dec-* mips-little-*
4054 riscos mips-*-riscos* mips-*-sysv*
4055 sonymips mips-sony-*
4056 sysv mips*-*-sysv4* (IRIX 5/6 not included)
4058 * REMOVED configurations and files
4060 SGI Irix-4.x mips-sgi-irix4 or iris4
4061 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
4062 Z8000 simulator z8k-zilog-none or z8ksim
4063 Matsushita MN10200 w/simulator mn10200-*-*
4064 H8/500 simulator h8500-hitachi-hms or h8500hms
4065 HP/PA running BSD hppa*-*-bsd*
4066 HP/PA running OSF/1 hppa*-*-osf*
4067 HP/PA Pro target hppa*-*-pro*
4068 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
4069 386BSD i[3456]86-*-bsd*
4070 Sequent family i[3456]86-sequent-sysv4*
4071 i[3456]86-sequent-sysv*
4072 i[3456]86-sequent-bsd*
4073 SPARC running LynxOS sparc-*-lynxos*
4074 SPARC running SunOS 4 sparc-*-sunos4*
4075 Tsqware Sparclet sparclet-*-*
4076 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
4078 *** Changes in GDB 6.0:
4082 Support for debugging the Objective-C programming language has been
4083 integrated into GDB.
4085 * New backtrace mechanism (includes DWARF 2 Call Frame Information).
4087 DWARF 2's Call Frame Information makes available compiler generated
4088 information that more exactly describes the program's run-time stack.
4089 By using this information, GDB is able to provide more robust stack
4092 The i386, amd64 (nee, x86-64), Alpha, m68hc11, ia64, and m32r targets
4093 have been updated to use a new backtrace mechanism which includes
4094 DWARF 2 CFI support.
4098 GDB's remote protocol has been extended to include support for hosted
4099 file I/O (where the remote target uses GDB's file system). See GDB's
4100 remote protocol documentation for details.
4102 * All targets using the new architecture framework.
4104 All of GDB's targets have been updated to use the new internal
4105 architecture framework. The way is now open for future GDB releases
4106 to include cross-architecture native debugging support (i386 on amd64,
4109 * GNU/Linux's Thread Local Storage (TLS)
4111 GDB now includes support for for the GNU/Linux implementation of
4112 per-thread variables.
4114 * GNU/Linux's Native POSIX Thread Library (NPTL)
4116 GDB's thread code has been updated to work with either the new
4117 GNU/Linux NPTL thread library or the older "LinuxThreads" library.
4119 * Separate debug info.
4121 GDB, in conjunction with BINUTILS, now supports a mechanism for
4122 automatically loading debug information from a separate file. Instead
4123 of shipping full debug and non-debug versions of system libraries,
4124 system integrators can now instead ship just the stripped libraries
4125 and optional debug files.
4127 * DWARF 2 Location Expressions
4129 DWARF 2 Location Expressions allow the compiler to more completely
4130 describe the location of variables (even in optimized code) to the
4133 GDB now includes preliminary support for location expressions (support
4134 for DW_OP_piece is still missing).
4138 A number of long standing bugs that caused GDB to die while starting a
4139 Java application have been fixed. GDB's Java support is now
4140 considered "useable".
4142 * GNU/Linux support for fork, vfork, and exec.
4144 The "catch fork", "catch exec", "catch vfork", and "set follow-fork-mode"
4145 commands are now implemented for GNU/Linux. They require a 2.5.x or later
4148 * GDB supports logging output to a file
4150 There are two new commands, "set logging" and "show logging", which can be
4151 used to capture GDB's output to a file.
4153 * The meaning of "detach" has changed for gdbserver
4155 The "detach" command will now resume the application, as documented. To
4156 disconnect from gdbserver and leave it stopped, use the new "disconnect"
4159 * d10v, m68hc11 `regs' command deprecated
4161 The `info registers' command has been updated so that it displays the
4162 registers using a format identical to the old `regs' command.
4166 A new command, "maint set profile on/off", has been added. This command can
4167 be used to enable or disable profiling while running GDB, to profile a
4168 session or a set of commands. In addition there is a new configure switch,
4169 "--enable-profiling", which will cause GDB to be compiled with profiling
4170 data, for more informative profiling results.
4172 * Default MI syntax changed to "mi2".
4174 The default MI (machine interface) syntax, enabled by the command line
4175 option "-i=mi", has been changed to "mi2". The previous MI syntax,
4176 "mi1", can be enabled by specifying the option "-i=mi1".
4178 Support for the original "mi0" syntax (included in GDB 5.0) has been
4181 Fix for gdb/192: removed extraneous space when displaying frame level.
4182 Fix for gdb/672: update changelist is now output in mi list format.
4183 Fix for gdb/702: a -var-assign that updates the value now shows up
4184 in a subsequent -var-update.
4186 * New native configurations.
4188 FreeBSD/amd64 x86_64-*-freebsd*
4190 * Multi-arched targets.
4192 HP/PA HPUX11 hppa*-*-hpux*
4193 Renesas M32R/D w/simulator m32r-*-elf*
4195 * OBSOLETE configurations and files
4197 Configurations that have been declared obsolete in this release have
4198 been commented out. Unless there is activity to revive these
4199 configurations, the next release of GDB will have their sources
4200 permanently REMOVED.
4202 Z8000 simulator z8k-zilog-none or z8ksim
4203 Matsushita MN10200 w/simulator mn10200-*-*
4204 H8/500 simulator h8500-hitachi-hms or h8500hms
4205 HP/PA running BSD hppa*-*-bsd*
4206 HP/PA running OSF/1 hppa*-*-osf*
4207 HP/PA Pro target hppa*-*-pro*
4208 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
4209 Sequent family i[3456]86-sequent-sysv4*
4210 i[3456]86-sequent-sysv*
4211 i[3456]86-sequent-bsd*
4212 Tsqware Sparclet sparclet-*-*
4213 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
4215 * REMOVED configurations and files
4218 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
4219 IBM AIX PS/2 i[3456]86-*-aix
4220 i386 running Mach 3.0 i[3456]86-*-mach3*
4221 i386 running Mach i[3456]86-*-mach*
4222 i386 running OSF/1 i[3456]86-*osf1mk*
4223 HP/Apollo 68k Family m68*-apollo*-sysv*,
4225 m68*-hp-bsd*, m68*-hp-hpux*
4226 Argonaut Risc Chip (ARC) arc-*-*
4227 Mitsubishi D30V d30v-*-*
4228 Fujitsu FR30 fr30-*-elf*
4229 OS/9000 i[34]86-*-os9k
4230 I960 with MON960 i960-*-coff
4232 * MIPS $fp behavior changed
4234 The convenience variable $fp, for the MIPS, now consistently returns
4235 the address of the current frame's base. Previously, depending on the
4236 context, $fp could refer to either $sp or the current frame's base
4237 address. See ``8.10 Registers'' in the manual ``Debugging with GDB:
4238 The GNU Source-Level Debugger''.
4240 *** Changes in GDB 5.3:
4242 * GNU/Linux shared library multi-threaded performance improved.
4244 When debugging a multi-threaded application on GNU/Linux, GDB now uses
4245 `/proc', in preference to `ptrace' for memory reads. This may result
4246 in an improvement in the start-up time of multi-threaded, shared
4247 library applications when run under GDB. One GDB user writes: ``loads
4248 shared libs like mad''.
4250 * ``gdbserver'' now supports multi-threaded applications on some targets
4252 Support for debugging multi-threaded applications which use
4253 the GNU/Linux LinuxThreads package has been added for
4254 arm*-*-linux*-gnu*, i[3456]86-*-linux*-gnu*, mips*-*-linux*-gnu*,
4255 powerpc*-*-linux*-gnu*, and sh*-*-linux*-gnu*.
4257 * GDB now supports C/C++ preprocessor macros.
4259 GDB now expands preprocessor macro invocations in C/C++ expressions,
4260 and provides various commands for showing macro definitions and how
4263 The new command `macro expand EXPRESSION' expands any macro
4264 invocations in expression, and shows the result.
4266 The new command `show macro MACRO-NAME' shows the definition of the
4267 macro named MACRO-NAME, and where it was defined.
4269 Most compilers don't include information about macros in the debugging
4270 information by default. In GCC 3.1, for example, you need to compile
4271 your program with the options `-gdwarf-2 -g3'. If the macro
4272 information is present in the executable, GDB will read it.
4274 * Multi-arched targets.
4276 DEC Alpha (partial) alpha*-*-*
4277 DEC VAX (partial) vax-*-*
4279 National Semiconductor NS32000 (partial) ns32k-*-*
4280 Motorola 68000 (partial) m68k-*-*
4281 Motorola MCORE mcore-*-*
4285 Fujitsu FRV architecture added by Red Hat frv*-*-*
4288 * New native configurations
4290 Alpha NetBSD alpha*-*-netbsd*
4291 SH NetBSD sh*-*-netbsdelf*
4292 MIPS NetBSD mips*-*-netbsd*
4293 UltraSPARC NetBSD sparc64-*-netbsd*
4295 * OBSOLETE configurations and files
4297 Configurations that have been declared obsolete in this release have
4298 been commented out. Unless there is activity to revive these
4299 configurations, the next release of GDB will have their sources
4300 permanently REMOVED.
4302 Mitsubishi D30V d30v-*-*
4303 OS/9000 i[34]86-*-os9k
4304 IBM AIX PS/2 i[3456]86-*-aix
4305 Fujitsu FR30 fr30-*-elf*
4306 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
4307 Argonaut Risc Chip (ARC) arc-*-*
4308 i386 running Mach 3.0 i[3456]86-*-mach3*
4309 i386 running Mach i[3456]86-*-mach*
4310 i386 running OSF/1 i[3456]86-*osf1mk*
4311 HP/Apollo 68k Family m68*-apollo*-sysv*,
4313 m68*-hp-bsd*, m68*-hp-hpux*
4314 I960 with MON960 i960-*-coff
4316 * OBSOLETE languages
4318 CHILL, a Pascal like language used by telecommunications companies.
4320 * REMOVED configurations and files
4322 AMD 29k family via UDI a29k-amd-udi, udi29k
4323 A29K VxWorks a29k-*-vxworks
4324 AMD 29000 embedded, using EBMON a29k-none-none
4325 AMD 29000 embedded with COFF a29k-none-coff
4326 AMD 29000 embedded with a.out a29k-none-aout
4328 testsuite/gdb.hp/gdb.threads-hp/ directory
4330 * New command "set max-user-call-depth <nnn>"
4332 This command allows the user to limit the call depth of user-defined
4333 commands. The default is 1024.
4335 * Changes in FreeBSD/i386 native debugging.
4337 Support for the "generate-core-file" has been added.
4339 * New commands "dump", "append", and "restore".
4341 These commands allow data to be copied from target memory
4342 to a bfd-format or binary file (dump and append), and back
4343 from a file into memory (restore).
4345 * Improved "next/step" support on multi-processor Alpha Tru64.
4347 The previous single-step mechanism could cause unpredictable problems,
4348 including the random appearance of SIGSEGV or SIGTRAP signals. The use
4349 of a software single-step mechanism prevents this.
4351 *** Changes in GDB 5.2.1:
4359 gdb/182: gdb/323: gdb/237: On alpha, gdb was reporting:
4360 mdebugread.c:2443: gdb-internal-error: sect_index_data not initialized
4361 Fix, by Joel Brobecker imported from mainline.
4363 gdb/439: gdb/291: On some ELF object files, gdb was reporting:
4364 dwarf2read.c:1072: gdb-internal-error: sect_index_text not initialize
4365 Fix, by Fred Fish, imported from mainline.
4367 Dwarf2 .debug_frame & .eh_frame handler improved in many ways.
4368 Surprisingly enough, it works now.
4369 By Michal Ludvig, imported from mainline.
4371 i386 hardware watchpoint support:
4372 avoid misses on second run for some targets.
4373 By Pierre Muller, imported from mainline.
4375 *** Changes in GDB 5.2:
4377 * New command "set trust-readonly-sections on[off]".
4379 This command is a hint that tells gdb that read-only sections
4380 really are read-only (ie. that their contents will not change).
4381 In this mode, gdb will go to the object file rather than the
4382 target to read memory from read-only sections (such as ".text").
4383 This can be a significant performance improvement on some
4384 (notably embedded) targets.
4386 * New command "generate-core-file" (or "gcore").
4388 This new gdb command allows the user to drop a core file of the child
4389 process state at any time. So far it's been implemented only for
4390 GNU/Linux and Solaris, but should be relatively easily ported to other
4391 hosts. Argument is core file name (defaults to core.<pid>).
4393 * New command line option
4395 GDB now accepts --pid or -p followed by a process id.
4397 * Change in command line behavior -- corefiles vs. process ids.
4399 There is a subtle behavior in the way in which GDB handles
4400 command line arguments. The first non-flag argument is always
4401 a program to debug, but the second non-flag argument may either
4402 be a corefile or a process id. Previously, GDB would attempt to
4403 open the second argument as a corefile, and if that failed, would
4404 issue a superfluous error message and then attempt to attach it as
4405 a process. Now, if the second argument begins with a non-digit,
4406 it will be treated as a corefile. If it begins with a digit,
4407 GDB will attempt to attach it as a process, and if no such process
4408 is found, will then attempt to open it as a corefile.
4410 * Changes in ARM configurations.
4412 Multi-arch support is enabled for all ARM configurations. The ARM/NetBSD
4413 configuration is fully multi-arch.
4415 * New native configurations
4417 ARM NetBSD arm*-*-netbsd*
4418 x86 OpenBSD i[3456]86-*-openbsd*
4419 AMD x86-64 running GNU/Linux x86_64-*-linux-*
4420 Sparc64 running FreeBSD sparc64-*-freebsd*
4424 Sanyo XStormy16 xstormy16-elf
4426 * OBSOLETE configurations and files
4428 Configurations that have been declared obsolete in this release have
4429 been commented out. Unless there is activity to revive these
4430 configurations, the next release of GDB will have their sources
4431 permanently REMOVED.
4433 AMD 29k family via UDI a29k-amd-udi, udi29k
4434 A29K VxWorks a29k-*-vxworks
4435 AMD 29000 embedded, using EBMON a29k-none-none
4436 AMD 29000 embedded with COFF a29k-none-coff
4437 AMD 29000 embedded with a.out a29k-none-aout
4439 testsuite/gdb.hp/gdb.threads-hp/ directory
4441 * REMOVED configurations and files
4443 TI TMS320C80 tic80-*-*
4445 PowerPC Solaris powerpcle-*-solaris*
4446 PowerPC Windows NT powerpcle-*-cygwin32
4447 PowerPC Netware powerpc-*-netware*
4448 Harris/CXUX m88k m88*-harris-cxux*
4449 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
4450 ns32k-utek-sysv* ns32k-utek-*
4451 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
4452 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
4453 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
4454 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
4455 Apple Macintosh (MPW) host and target N/A host, powerpc-*-macos*
4457 * Changes to command line processing
4459 The new `--args' feature can be used to specify command-line arguments
4460 for the inferior from gdb's command line.
4462 * Changes to key bindings
4464 There is a new `operate-and-get-next' function bound to `C-o'.
4466 *** Changes in GDB 5.1.1
4468 Fix compile problem on DJGPP.
4470 Fix a problem with floating-point registers on the i386 being
4473 Fix to stop GDB crashing on .debug_str debug info.
4475 Numerous documentation fixes.
4477 Numerous testsuite fixes.
4479 *** Changes in GDB 5.1:
4481 * New native configurations
4483 Alpha FreeBSD alpha*-*-freebsd*
4484 x86 FreeBSD 3.x and 4.x i[3456]86*-freebsd[34]*
4485 MIPS GNU/Linux mips*-*-linux*
4486 MIPS SGI Irix 6.x mips*-sgi-irix6*
4487 ia64 AIX ia64-*-aix*
4488 s390 and s390x GNU/Linux {s390,s390x}-*-linux*
4492 Motorola 68HC11 and 68HC12 m68hc11-elf
4494 UltraSparc running GNU/Linux sparc64-*-linux*
4496 * OBSOLETE configurations and files
4498 x86 FreeBSD before 2.2 i[3456]86*-freebsd{1,2.[01]}*,
4499 Harris/CXUX m88k m88*-harris-cxux*
4500 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
4501 ns32k-utek-sysv* ns32k-utek-*
4502 TI TMS320C80 tic80-*-*
4504 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
4505 PowerPC Solaris powerpcle-*-solaris*
4506 PowerPC Windows NT powerpcle-*-cygwin32
4507 PowerPC Netware powerpc-*-netware*
4508 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
4509 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
4510 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
4511 Apple Macintosh (MPW) host N/A
4513 stuff.c (Program to stuff files into a specially prepared space in kdb)
4514 kdb-start.c (Main loop for the standalone kernel debugger)
4516 Configurations that have been declared obsolete in this release have
4517 been commented out. Unless there is activity to revive these
4518 configurations, the next release of GDB will have their sources
4519 permanently REMOVED.
4521 * REMOVED configurations and files
4523 Altos 3068 m68*-altos-*
4524 Convex c1-*-*, c2-*-*
4526 ARM RISCix arm-*-* (as host)
4530 * GDB has been converted to ISO C.
4532 GDB's source code has been converted to ISO C. In particular, the
4533 sources are fully protoized, and rely on standard headers being
4538 * "info symbol" works on platforms which use COFF, ECOFF, XCOFF, and NLM.
4540 * The MI enabled by default.
4542 The new machine oriented interface (MI) introduced in GDB 5.0 has been
4543 revised and enabled by default. Packages which use GDB as a debugging
4544 engine behind a UI or another front end are encouraged to switch to
4545 using the GDB/MI interface, instead of the old annotations interface
4546 which is now deprecated.
4548 * Support for debugging Pascal programs.
4550 GDB now includes support for debugging Pascal programs. The following
4551 main features are supported:
4553 - Pascal-specific data types such as sets;
4555 - automatic recognition of Pascal sources based on file-name
4558 - Pascal-style display of data types, variables, and functions;
4560 - a Pascal expression parser.
4562 However, some important features are not yet supported.
4564 - Pascal string operations are not supported at all;
4566 - there are some problems with boolean types;
4568 - Pascal type hexadecimal constants are not supported
4569 because they conflict with the internal variables format;
4571 - support for Pascal objects and classes is not full yet;
4573 - unlike Pascal, GDB is case-sensitive for symbol names.
4575 * Changes in completion.
4577 Commands such as `shell', `run' and `set args', which pass arguments
4578 to inferior programs, now complete on file names, similar to what
4579 users expect at the shell prompt.
4581 Commands which accept locations, such as `disassemble', `print',
4582 `breakpoint', `until', etc. now complete on filenames as well as
4583 program symbols. Thus, if you type "break foob TAB", and the source
4584 files linked into the programs include `foobar.c', that file name will
4585 be one of the candidates for completion. However, file names are not
4586 considered for completion after you typed a colon that delimits a file
4587 name from a name of a function in that file, as in "break foo.c:bar".
4589 `set demangle-style' completes on available demangling styles.
4591 * New platform-independent commands:
4593 It is now possible to define a post-hook for a command as well as a
4594 hook that runs before the command. For more details, see the
4595 documentation of `hookpost' in the GDB manual.
4597 * Changes in GNU/Linux native debugging.
4599 Support for debugging multi-threaded programs has been completely
4600 revised for all platforms except m68k and sparc. You can now debug as
4601 many threads as your system allows you to have.
4603 Attach/detach is supported for multi-threaded programs.
4605 Support for SSE registers was added for x86. This doesn't work for
4606 multi-threaded programs though.
4608 * Changes in MIPS configurations.
4610 Multi-arch support is enabled for all MIPS configurations.
4612 GDB can now be built as native debugger on SGI Irix 6.x systems for
4613 debugging n32 executables. (Debugging 64-bit executables is not yet
4616 * Unified support for hardware watchpoints in all x86 configurations.
4618 Most (if not all) native x86 configurations support hardware-assisted
4619 breakpoints and watchpoints in a unified manner. This support
4620 implements debug register sharing between watchpoints, which allows to
4621 put a virtually infinite number of watchpoints on the same address,
4622 and also supports watching regions up to 16 bytes with several debug
4625 The new maintenance command `maintenance show-debug-regs' toggles
4626 debugging print-outs in functions that insert, remove, and test
4627 watchpoints and hardware breakpoints.
4629 * Changes in the DJGPP native configuration.
4631 New command ``info dos sysinfo'' displays assorted information about
4632 the CPU, OS, memory, and DPMI server.
4634 New commands ``info dos gdt'', ``info dos ldt'', and ``info dos idt''
4635 display information about segment descriptors stored in GDT, LDT, and
4638 New commands ``info dos pde'' and ``info dos pte'' display entries
4639 from Page Directory and Page Tables (for now works with CWSDPMI only).
4640 New command ``info dos address-pte'' displays the Page Table entry for
4641 a given linear address.
4643 GDB can now pass command lines longer than 126 characters to the
4644 program being debugged (requires an update to the libdbg.a library
4645 which is part of the DJGPP development kit).
4647 DWARF2 debug info is now supported.
4649 It is now possible to `step' and `next' through calls to `longjmp'.
4651 * Changes in documentation.
4653 All GDB documentation was converted to GFDL, the GNU Free
4654 Documentation License.
4656 Tracepoints-related commands are now fully documented in the GDB
4659 TUI, the Text-mode User Interface, is now documented in the manual.
4661 Tracepoints-related commands are now fully documented in the GDB
4664 The "GDB Internals" manual now has an index. It also includes
4665 documentation of `ui_out' functions, GDB coding standards, x86
4666 hardware watchpoints, and memory region attributes.
4668 * GDB's version number moved to ``version.in''
4670 The Makefile variable VERSION has been replaced by the file
4671 ``version.in''. People creating GDB distributions should update the
4672 contents of this file.
4676 GUD support is now a standard part of the EMACS distribution.
4678 *** Changes in GDB 5.0:
4680 * Improved support for debugging FP programs on x86 targets
4682 Unified and much-improved support for debugging floating-point
4683 programs on all x86 targets. In particular, ``info float'' now
4684 displays the FP registers in the same format on all x86 targets, with
4685 greater level of detail.
4687 * Improvements and bugfixes in hardware-assisted watchpoints
4689 It is now possible to watch array elements, struct members, and
4690 bitfields with hardware-assisted watchpoints. Data-read watchpoints
4691 on x86 targets no longer erroneously trigger when the address is
4694 * Improvements in the native DJGPP version of GDB
4696 The distribution now includes all the scripts and auxiliary files
4697 necessary to build the native DJGPP version on MS-DOS/MS-Windows
4698 machines ``out of the box''.
4700 The DJGPP version can now debug programs that use signals. It is
4701 possible to catch signals that happened in the debuggee, deliver
4702 signals to it, interrupt it with Ctrl-C, etc. (Previously, a signal
4703 would kill the program being debugged.) Programs that hook hardware
4704 interrupts (keyboard, timer, etc.) can also be debugged.
4706 It is now possible to debug DJGPP programs that redirect their
4707 standard handles or switch them to raw (as opposed to cooked) mode, or
4708 even close them. The command ``run < foo > bar'' works as expected,
4709 and ``info terminal'' reports useful information about the debuggee's
4710 terminal, including raw/cooked mode, redirection, etc.
4712 The DJGPP version now uses termios functions for console I/O, which
4713 enables debugging graphics programs. Interrupting GDB with Ctrl-C
4716 DOS-style file names with drive letters are now fully supported by
4719 It is now possible to debug DJGPP programs that switch their working
4720 directory. It is also possible to rerun the debuggee any number of
4721 times without restarting GDB; thus, you can use the same setup,
4722 breakpoints, etc. for many debugging sessions.
4724 * New native configurations
4726 ARM GNU/Linux arm*-*-linux*
4727 PowerPC GNU/Linux powerpc-*-linux*
4731 Motorola MCore mcore-*-*
4732 x86 VxWorks i[3456]86-*-vxworks*
4733 PowerPC VxWorks powerpc-*-vxworks*
4734 TI TMS320C80 tic80-*-*
4736 * OBSOLETE configurations
4738 Altos 3068 m68*-altos-*
4739 Convex c1-*-*, c2-*-*
4741 ARM RISCix arm-*-* (as host)
4744 Configurations that have been declared obsolete will be commented out,
4745 but the code will be left in place. If there is no activity to revive
4746 these configurations before the next release of GDB, the sources will
4747 be permanently REMOVED.
4749 * Gould support removed
4751 Support for the Gould PowerNode and NP1 has been removed.
4753 * New features for SVR4
4755 On SVR4 native platforms (such as Solaris), if you attach to a process
4756 without first loading a symbol file, GDB will now attempt to locate and
4757 load symbols from the running process's executable file.
4759 * Many C++ enhancements
4761 C++ support has been greatly improved. Overload resolution now works properly
4762 in almost all cases. RTTI support is on the way.
4764 * Remote targets can connect to a sub-program
4766 A popen(3) style serial-device has been added. This device starts a
4767 sub-process (such as a stand-alone simulator) and then communicates
4768 with that. The sub-program to run is specified using the syntax
4769 ``|<program> <args>'' vis:
4771 (gdb) set remotedebug 1
4772 (gdb) target extended-remote |mn10300-elf-sim program-args
4774 * MIPS 64 remote protocol
4776 A long standing bug in the mips64 remote protocol where by GDB
4777 expected certain 32 bit registers (ex SR) to be transfered as 32
4778 instead of 64 bits has been fixed.
4780 The command ``set remote-mips64-transfers-32bit-regs on'' has been
4781 added to provide backward compatibility with older versions of GDB.
4783 * ``set remotebinarydownload'' replaced by ``set remote X-packet''
4785 The command ``set remotebinarydownload'' command has been replaced by
4786 ``set remote X-packet''. Other commands in ``set remote'' family
4787 include ``set remote P-packet''.
4789 * Breakpoint commands accept ranges.
4791 The breakpoint commands ``enable'', ``disable'', and ``delete'' now
4792 accept a range of breakpoints, e.g. ``5-7''. The tracepoint command
4793 ``tracepoint passcount'' also accepts a range of tracepoints.
4795 * ``apropos'' command added.
4797 The ``apropos'' command searches through command names and
4798 documentation strings, printing out matches, making it much easier to
4799 try to find a command that does what you are looking for.
4803 A new machine oriented interface (MI) has been added to GDB. This
4804 interface is designed for debug environments running GDB as a separate
4805 process. This is part of the long term libGDB project. See the
4806 "GDB/MI" chapter of the GDB manual for further information. It can be
4807 enabled by configuring with:
4809 .../configure --enable-gdbmi
4811 *** Changes in GDB-4.18:
4813 * New native configurations
4815 HP-UX 10.20 hppa*-*-hpux10.20
4816 HP-UX 11.x hppa*-*-hpux11.0*
4817 M68K GNU/Linux m68*-*-linux*
4821 Fujitsu FR30 fr30-*-elf*
4822 Intel StrongARM strongarm-*-*
4823 Mitsubishi D30V d30v-*-*
4825 * OBSOLETE configurations
4827 Gould PowerNode, NP1 np1-*-*, pn-*-*
4829 Configurations that have been declared obsolete will be commented out,
4830 but the code will be left in place. If there is no activity to revive
4831 these configurations before the next release of GDB, the sources will
4832 be permanently REMOVED.
4836 As a compatibility experiment, GDB's source files buildsym.h and
4837 buildsym.c have been converted to pure standard C, no longer
4838 containing any K&R compatibility code. We believe that all systems in
4839 use today either come with a standard C compiler, or have a GCC port
4840 available. If this is not true, please report the affected
4841 configuration to bug-gdb@gnu.org immediately. See the README file for
4842 information about getting a standard C compiler if you don't have one
4847 GDB now uses readline 2.2.
4849 * set extension-language
4851 You can now control the mapping between filename extensions and source
4852 languages by using the `set extension-language' command. For instance,
4853 you can ask GDB to treat .c files as C++ by saying
4854 set extension-language .c c++
4855 The command `info extensions' lists all of the recognized extensions
4856 and their associated languages.
4858 * Setting processor type for PowerPC and RS/6000
4860 When GDB is configured for a powerpc*-*-* or an rs6000*-*-* target,
4861 you can use the `set processor' command to specify what variant of the
4862 PowerPC family you are debugging. The command
4866 sets the PowerPC/RS6000 variant to NAME. GDB knows about the
4867 following PowerPC and RS6000 variants:
4869 ppc-uisa PowerPC UISA - a PPC processor as viewed by user-level code
4870 rs6000 IBM RS6000 ("POWER") architecture, user-level view
4872 403GC IBM PowerPC 403GC
4873 505 Motorola PowerPC 505
4874 860 Motorola PowerPC 860 or 850
4875 601 Motorola PowerPC 601
4876 602 Motorola PowerPC 602
4877 603 Motorola/IBM PowerPC 603 or 603e
4878 604 Motorola PowerPC 604 or 604e
4879 750 Motorola/IBM PowerPC 750 or 750
4881 At the moment, this command just tells GDB what to name the
4882 special-purpose processor registers. Since almost all the affected
4883 registers are inaccessible to user-level programs, this command is
4884 only useful for remote debugging in its present form.
4888 Thanks to a major code donation from Hewlett-Packard, GDB now has much
4889 more extensive support for HP-UX. Added features include shared
4890 library support, kernel threads and hardware watchpoints for 11.00,
4891 support for HP's ANSI C and C++ compilers, and a compatibility mode
4892 for xdb and dbx commands.
4896 HP's donation includes the new concept of catchpoints, which is a
4897 generalization of the old catch command. On HP-UX, it is now possible
4898 to catch exec, fork, and vfork, as well as library loading.
4900 This means that the existing catch command has changed; its first
4901 argument now specifies the type of catch to be set up. See the
4902 output of "help catch" for a list of catchpoint types.
4904 * Debugging across forks
4906 On HP-UX, you can choose which process to debug when a fork() happens
4911 HP has donated a curses-based terminal user interface (TUI). To get
4912 it, build with --enable-tui. Although this can be enabled for any
4913 configuration, at present it only works for native HP debugging.
4915 * GDB remote protocol additions
4917 A new protocol packet 'X' that writes binary data is now available.
4918 Default behavior is to try 'X', then drop back to 'M' if the stub
4919 fails to respond. The settable variable `remotebinarydownload'
4920 allows explicit control over the use of 'X'.
4922 For 64-bit targets, the memory packets ('M' and 'm') can now contain a
4923 full 64-bit address. The command
4925 set remoteaddresssize 32
4927 can be used to revert to the old behaviour. For existing remote stubs
4928 the change should not be noticed, as the additional address information
4931 In order to assist in debugging stubs, you may use the maintenance
4932 command `packet' to send any text string to the stub. For instance,
4934 maint packet heythere
4936 sends the packet "$heythere#<checksum>". Note that it is very easy to
4937 disrupt a debugging session by sending the wrong packet at the wrong
4940 The compare-sections command allows you to compare section data on the
4941 target to what is in the executable file without uploading or
4942 downloading, by comparing CRC checksums.
4944 * Tracing can collect general expressions
4946 You may now collect general expressions at tracepoints. This requires
4947 further additions to the target-side stub; see tracepoint.c and
4948 doc/agentexpr.texi for further details.
4950 * mask-address variable for Mips
4952 For Mips targets, you may control the zeroing of the upper 32 bits of
4953 a 64-bit address by entering `set mask-address on'. This is mainly
4954 of interest to users of embedded R4xxx and R5xxx processors.
4956 * Higher serial baud rates
4958 GDB's serial code now allows you to specify baud rates 57600, 115200,
4959 230400, and 460800 baud. (Note that your host system may not be able
4960 to achieve all of these rates.)
4964 The i960 configuration now includes an initial implementation of a
4965 builtin simulator, contributed by Jim Wilson.
4968 *** Changes in GDB-4.17:
4970 * New native configurations
4972 Alpha GNU/Linux alpha*-*-linux*
4973 Unixware 2.x i[3456]86-unixware2*
4974 Irix 6.x mips*-sgi-irix6*
4975 PowerPC GNU/Linux powerpc-*-linux*
4976 PowerPC Solaris powerpcle-*-solaris*
4977 Sparc GNU/Linux sparc-*-linux*
4978 Motorola sysV68 R3V7.1 m68k-motorola-sysv
4982 Argonaut Risc Chip (ARC) arc-*-*
4983 Hitachi H8/300S h8300*-*-*
4984 Matsushita MN10200 w/simulator mn10200-*-*
4985 Matsushita MN10300 w/simulator mn10300-*-*
4986 MIPS NEC VR4100 mips64*vr4100*{,el}-*-elf*
4987 MIPS NEC VR5000 mips64*vr5000*{,el}-*-elf*
4988 MIPS Toshiba TX39 mips64*tx39*{,el}-*-elf*
4989 Mitsubishi D10V w/simulator d10v-*-*
4990 Mitsubishi M32R/D w/simulator m32r-*-elf*
4991 Tsqware Sparclet sparclet-*-*
4992 NEC V850 w/simulator v850-*-*
4994 * New debugging protocols
4996 ARM with RDI protocol arm*-*-*
4997 M68K with dBUG monitor m68*-*-{aout,coff,elf}
4998 DDB and LSI variants of PMON protocol mips*-*-*
4999 PowerPC with DINK32 monitor powerpc{,le}-*-eabi
5000 PowerPC with SDS protocol powerpc{,le}-*-eabi
5001 Macraigor OCD (Wiggler) devices powerpc{,le}-*-eabi
5005 All configurations can now understand and use the DWARF 2 debugging
5006 format. The choice is automatic, if the symbol file contains DWARF 2
5011 GDB now includes basic Java language support. This support is
5012 only useful with Java compilers that produce native machine code.
5014 * solib-absolute-prefix and solib-search-path
5016 For SunOS and SVR4 shared libraries, you may now set the prefix for
5017 loading absolute shared library symbol files, and the search path for
5018 locating non-absolute shared library symbol files.
5020 * Live range splitting
5022 GDB can now effectively debug code for which GCC has performed live
5023 range splitting as part of its optimization. See gdb/doc/LRS for
5024 more details on the expected format of the stabs information.
5028 GDB's support for the GNU Hurd, including thread debugging, has been
5029 updated to work with current versions of the Hurd.
5033 GDB's ARM target configuration now handles the ARM7T (Thumb) 16-bit
5034 instruction set. ARM GDB automatically detects when Thumb
5035 instructions are in use, and adjusts disassembly and backtracing
5040 GDB's MIPS target configurations now handle the MIP16 16-bit
5045 GDB now includes support for overlays; if an executable has been
5046 linked such that multiple sections are based at the same address, GDB
5047 will decide which section to use for symbolic info. You can choose to
5048 control the decision manually, using overlay commands, or implement
5049 additional target-side support and use "overlay load-target" to bring
5050 in the overlay mapping. Do "help overlay" for more detail.
5054 The command "info symbol <address>" displays information about
5055 the symbol at the specified address.
5059 The standard remote protocol now includes an extension that allows
5060 asynchronous collection and display of trace data. This requires
5061 extensive support in the target-side debugging stub. Tracing mode
5062 includes a new interaction mode in GDB and new commands: see the
5063 file tracepoint.c for more details.
5067 Configurations for embedded MIPS now include a simulator contributed
5068 by Cygnus Solutions. The simulator supports the instruction sets
5069 of most MIPS variants.
5073 Sparc configurations may now include the ERC32 simulator contributed
5074 by the European Space Agency. The simulator is not built into
5075 Sparc targets by default; configure with --enable-sim to include it.
5079 For target configurations that may include multiple variants of a
5080 basic architecture (such as MIPS and SH), you may now set the
5081 architecture explicitly. "set arch" sets, "info arch" lists
5082 the possible architectures.
5084 *** Changes in GDB-4.16:
5086 * New native configurations
5088 Windows 95, x86 Windows NT i[345]86-*-cygwin32
5089 M68K NetBSD m68k-*-netbsd*
5090 PowerPC AIX 4.x powerpc-*-aix*
5091 PowerPC MacOS powerpc-*-macos*
5092 PowerPC Windows NT powerpcle-*-cygwin32
5093 RS/6000 AIX 4.x rs6000-*-aix4*
5097 ARM with RDP protocol arm-*-*
5098 I960 with MON960 i960-*-coff
5099 MIPS VxWorks mips*-*-vxworks*
5100 MIPS VR4300 with PMON mips64*vr4300{,el}-*-elf*
5101 PowerPC with PPCBUG monitor powerpc{,le}-*-eabi*
5103 Matra Sparclet sparclet-*-*
5107 The powerpc-eabi configuration now includes the PSIM simulator,
5108 contributed by Andrew Cagney, with assistance from Mike Meissner.
5109 PSIM is a very elaborate model of the PowerPC, including not only
5110 basic instruction set execution, but also details of execution unit
5111 performance and I/O hardware. See sim/ppc/README for more details.
5115 GDB now works with Solaris 2.5.
5117 * Windows 95/NT native
5119 GDB will now work as a native debugger on Windows 95 and Windows NT.
5120 To build it from source, you must use the "gnu-win32" environment,
5121 which uses a DLL to emulate enough of Unix to run the GNU tools.
5122 Further information, binaries, and sources are available at
5123 ftp.cygnus.com, under pub/gnu-win32.
5125 * dont-repeat command
5127 If a user-defined command includes the command `dont-repeat', then the
5128 command will not be repeated if the user just types return. This is
5129 useful if the command is time-consuming to run, so that accidental
5130 extra keystrokes don't run the same command many times.
5132 * Send break instead of ^C
5134 The standard remote protocol now includes an option to send a break
5135 rather than a ^C to the target in order to interrupt it. By default,
5136 GDB will send ^C; to send a break, set the variable `remotebreak' to 1.
5138 * Remote protocol timeout
5140 The standard remote protocol includes a new variable `remotetimeout'
5141 that allows you to set the number of seconds before GDB gives up trying
5142 to read from the target. The default value is 2.
5144 * Automatic tracking of dynamic object loading (HPUX and Solaris only)
5146 By default GDB will automatically keep track of objects as they are
5147 loaded and unloaded by the dynamic linker. By using the command `set
5148 stop-on-solib-events 1' you can arrange for GDB to stop the inferior
5149 when shared library events occur, thus allowing you to set breakpoints
5150 in shared libraries which are explicitly loaded by the inferior.
5152 Note this feature does not work on hpux8. On hpux9 you must link
5153 /usr/lib/end.o into your program. This feature should work
5154 automatically on hpux10.
5156 * Irix 5.x hardware watchpoint support
5158 Irix 5 configurations now support the use of hardware watchpoints.
5160 * Mips protocol "SYN garbage limit"
5162 When debugging a Mips target using the `target mips' protocol, you
5163 may set the number of characters that GDB will ignore by setting
5164 the `syn-garbage-limit'. A value of -1 means that GDB will ignore
5165 every character. The default value is 1050.
5167 * Recording and replaying remote debug sessions
5169 If you set `remotelogfile' to the name of a file, gdb will write to it
5170 a recording of a remote debug session. This recording may then be
5171 replayed back to gdb using "gdbreplay". See gdbserver/README for
5172 details. This is useful when you have a problem with GDB while doing
5173 remote debugging; you can make a recording of the session and send it
5174 to someone else, who can then recreate the problem.
5176 * Speedups for remote debugging
5178 GDB includes speedups for downloading and stepping MIPS systems using
5179 the IDT monitor, fast downloads to the Hitachi SH E7000 emulator,
5180 and more efficient S-record downloading.
5182 * Memory use reductions and statistics collection
5184 GDB now uses less memory and reports statistics about memory usage.
5185 Try the `maint print statistics' command, for example.
5187 *** Changes in GDB-4.15:
5189 * Psymtabs for XCOFF
5191 The symbol reader for AIX GDB now uses partial symbol tables. This
5192 can greatly improve startup time, especially for large executables.
5194 * Remote targets use caching
5196 Remote targets now use a data cache to speed up communication with the
5197 remote side. The data cache could lead to incorrect results because
5198 it doesn't know about volatile variables, thus making it impossible to
5199 debug targets which use memory mapped I/O devices. `set remotecache
5200 off' turns the the data cache off.
5202 * Remote targets may have threads
5204 The standard remote protocol now includes support for multiple threads
5205 in the target system, using new protocol commands 'H' and 'T'. See
5206 gdb/remote.c for details.
5210 If GDB is configured with `--enable-netrom', then it will include
5211 support for the NetROM ROM emulator from XLNT Designs. The NetROM
5212 acts as though it is a bank of ROM on the target board, but you can
5213 write into it over the network. GDB's support consists only of
5214 support for fast loading into the emulated ROM; to debug, you must use
5215 another protocol, such as standard remote protocol. The usual
5216 sequence is something like
5218 target nrom <netrom-hostname>
5220 target remote <netrom-hostname>:1235
5224 GDB now includes support for the Apple Macintosh, as a host only. It
5225 may be run as either an MPW tool or as a standalone application, and
5226 it can debug through the serial port. All the usual GDB commands are
5227 available, but to the target command, you must supply "serial" as the
5228 device type instead of "/dev/ttyXX". See mpw-README in the main
5229 directory for more information on how to build. The MPW configuration
5230 scripts */mpw-config.in support only a few targets, and only the
5231 mips-idt-ecoff target has been tested.
5235 GDB configuration now uses autoconf. This is not user-visible,
5236 but does simplify configuration and building.
5240 GDB now supports hpux10.
5242 *** Changes in GDB-4.14:
5244 * New native configurations
5246 x86 FreeBSD i[345]86-*-freebsd
5247 x86 NetBSD i[345]86-*-netbsd
5248 NS32k NetBSD ns32k-*-netbsd
5249 Sparc NetBSD sparc-*-netbsd
5253 A29K VxWorks a29k-*-vxworks
5254 HP PA PRO embedded (WinBond W89K & Oki OP50N) hppa*-*-pro*
5255 CPU32 EST-300 emulator m68*-*-est*
5256 PowerPC ELF powerpc-*-elf
5259 * Alpha OSF/1 support for procfs
5261 GDB now supports procfs under OSF/1-2.x and higher, which makes it
5262 possible to attach to running processes. As the mounting of the /proc
5263 filesystem is optional on the Alpha, GDB automatically determines
5264 the availability of /proc during startup. This can lead to problems
5265 if /proc is unmounted after GDB has been started.
5267 * Arguments to user-defined commands
5269 User commands may accept up to 10 arguments separated by whitespace.
5270 Arguments are accessed within the user command via $arg0..$arg9. A
5273 print $arg0 + $arg1 + $arg2
5275 To execute the command use:
5278 Defines the command "adder" which prints the sum of its three arguments.
5279 Note the arguments are text substitutions, so they may reference variables,
5280 use complex expressions, or even perform inferior function calls.
5282 * New `if' and `while' commands
5284 This makes it possible to write more sophisticated user-defined
5285 commands. Both commands take a single argument, which is the
5286 expression to evaluate, and must be followed by the commands to
5287 execute, one per line, if the expression is nonzero, the list being
5288 terminated by the word `end'. The `if' command list may include an
5289 `else' word, which causes the following commands to be executed only
5290 if the expression is zero.
5292 * Fortran source language mode
5294 GDB now includes partial support for Fortran 77. It will recognize
5295 Fortran programs and can evaluate a subset of Fortran expressions, but
5296 variables and functions may not be handled correctly. GDB will work
5297 with G77, but does not yet know much about symbols emitted by other
5300 * Better HPUX support
5302 Most debugging facilities now work on dynamic executables for HPPAs
5303 running hpux9 or later. You can attach to running dynamically linked
5304 processes, but by default the dynamic libraries will be read-only, so
5305 for instance you won't be able to put breakpoints in them. To change
5306 that behavior do the following before running the program:
5312 This will cause the libraries to be mapped private and read-write.
5313 To revert to the normal behavior, do this:
5319 You cannot set breakpoints or examine data in the library until after
5320 the library is loaded if the function/data symbols do not have
5323 GDB can now also read debug symbols produced by the HP C compiler on
5324 HPPAs (sorry, no C++, Fortran or 68k support).
5326 * Target byte order now dynamically selectable
5328 You can choose which byte order to use with a target system, via the
5329 commands "set endian big" and "set endian little", and you can see the
5330 current setting by using "show endian". You can also give the command
5331 "set endian auto", in which case GDB will use the byte order
5332 associated with the executable. Currently, only embedded MIPS
5333 configurations support dynamic selection of target byte order.
5335 * New DOS host serial code
5337 This version uses DPMI interrupts to handle buffered I/O, so you
5338 no longer need to run asynctsr when debugging boards connected to
5341 *** Changes in GDB-4.13:
5343 * New "complete" command
5345 This lists all the possible completions for the rest of the line, if it
5346 were to be given as a command itself. This is intended for use by emacs.
5348 * Trailing space optional in prompt
5350 "set prompt" no longer adds a space for you after the prompt you set. This
5351 allows you to set a prompt which ends in a space or one that does not.
5353 * Breakpoint hit counts
5355 "info break" now displays a count of the number of times the breakpoint
5356 has been hit. This is especially useful in conjunction with "ignore"; you
5357 can ignore a large number of breakpoint hits, look at the breakpoint info
5358 to see how many times the breakpoint was hit, then run again, ignoring one
5359 less than that number, and this will get you quickly to the last hit of
5362 * Ability to stop printing at NULL character
5364 "set print null-stop" will cause GDB to stop printing the characters of
5365 an array when the first NULL is encountered. This is useful when large
5366 arrays actually contain only short strings.
5368 * Shared library breakpoints
5370 In SunOS 4.x, SVR4, and Alpha OSF/1 configurations, you can now set
5371 breakpoints in shared libraries before the executable is run.
5373 * Hardware watchpoints
5375 There is a new hardware breakpoint for the watch command for sparclite
5376 targets. See gdb/sparclite/hw_breakpoint.note.
5378 Hardware watchpoints are also now supported under GNU/Linux.
5382 Annotations have been added. These are for use with graphical interfaces,
5383 and are still experimental. Currently only gdba.el uses these.
5385 * Improved Irix 5 support
5387 GDB now works properly with Irix 5.2.
5389 * Improved HPPA support
5391 GDB now works properly with the latest GCC and GAS.
5393 * New native configurations
5395 Sequent PTX4 i[34]86-sequent-ptx4
5396 HPPA running OSF/1 hppa*-*-osf*
5397 Atari TT running SVR4 m68*-*-sysv4*
5398 RS/6000 LynxOS rs6000-*-lynxos*
5402 OS/9000 i[34]86-*-os9k
5403 MIPS R4000 mips64*{,el}-*-{ecoff,elf}
5406 * Hitachi SH7000 and E7000-PC ICE support
5408 There is now support for communicating with the Hitachi E7000-PC ICE.
5409 This is available automatically when GDB is configured for the SH.
5413 As usual, a variety of small fixes and improvements, both generic
5414 and configuration-specific. See the ChangeLog for more detail.
5416 *** Changes in GDB-4.12:
5418 * Irix 5 is now supported
5422 GDB-4.12 on the HPPA has a number of changes which make it unable
5423 to debug the output from the currently released versions of GCC and
5424 GAS (GCC 2.5.8 and GAS-2.2 or PAGAS-1.36). Until the next major release
5425 of GCC and GAS, versions of these tools designed to work with GDB-4.12
5426 can be retrieved via anonymous ftp from jaguar.cs.utah.edu:/dist.
5429 *** Changes in GDB-4.11:
5431 * User visible changes:
5435 The "set remotedebug" option is now consistent between the mips remote
5436 target, remote targets using the gdb-specific protocol, UDI (AMD's
5437 debug protocol for the 29k) and the 88k bug monitor. It is now an
5438 integer specifying a debug level (normally 0 or 1, but 2 means more
5439 debugging info for the mips target).
5441 * DEC Alpha native support
5443 GDB now works on the DEC Alpha. GCC 2.4.5 does not produce usable
5444 debug info, but GDB works fairly well with the DEC compiler and should
5445 work with a future GCC release. See the README file for a few
5446 Alpha-specific notes.
5448 * Preliminary thread implementation
5450 GDB now has preliminary thread support for both SGI/Irix and LynxOS.
5452 * LynxOS native and target support for 386
5454 This release has been hosted on LynxOS 2.2, and also can be configured
5455 to remotely debug programs running under LynxOS (see gdb/gdbserver/README
5458 * Improvements in C++ mangling/demangling.
5460 This release has much better g++ debugging, specifically in name
5461 mangling/demangling, virtual function calls, print virtual table,
5462 call methods, ...etc.
5464 *** Changes in GDB-4.10:
5466 * User visible changes:
5468 Remote debugging using the GDB-specific (`target remote') protocol now
5469 supports the `load' command. This is only useful if you have some
5470 other way of getting the stub to the target system, and you can put it
5471 somewhere in memory where it won't get clobbered by the download.
5473 Filename completion now works.
5475 When run under emacs mode, the "info line" command now causes the
5476 arrow to point to the line specified. Also, "info line" prints
5477 addresses in symbolic form (as well as hex).
5479 All vxworks based targets now support a user settable option, called
5480 vxworks-timeout. This option represents the number of seconds gdb
5481 should wait for responses to rpc's. You might want to use this if
5482 your vxworks target is, perhaps, a slow software simulator or happens
5483 to be on the far side of a thin network line.
5487 This release contains support for using a DEC alpha as a GDB host for
5488 cross debugging. Native alpha debugging is not supported yet.
5491 *** Changes in GDB-4.9:
5495 This is the first GDB release which is accompanied by a matching testsuite.
5496 The testsuite requires installation of dejagnu, which should be available
5497 via ftp from most sites that carry GNU software.
5501 'Cfront' style demangling has had its name changed to 'ARM' style, to
5502 emphasize that it was written from the specifications in the C++ Annotated
5503 Reference Manual, not necessarily to be compatible with AT&T cfront. Despite
5504 disclaimers, it still generated too much confusion with users attempting to
5505 use gdb with AT&T cfront.
5509 GDB now uses a standard remote interface to a simulator library.
5510 So far, the library contains simulators for the Zilog Z8001/2, the
5511 Hitachi H8/300, H8/500 and Super-H.
5513 * New targets supported
5515 H8/300 simulator h8300-hitachi-hms or h8300hms
5516 H8/500 simulator h8500-hitachi-hms or h8500hms
5517 SH simulator sh-hitachi-hms or sh
5518 Z8000 simulator z8k-zilog-none or z8ksim
5519 IDT MIPS board over serial line mips-idt-ecoff
5521 Cross-debugging to GO32 targets is supported. It requires a custom
5522 version of the i386-stub.c module which is integrated with the
5523 GO32 memory extender.
5525 * New remote protocols
5527 MIPS remote debugging protocol.
5529 * New source languages supported
5531 This version includes preliminary support for Chill, a Pascal like language
5532 used by telecommunications companies. Chill support is also being integrated
5533 into the GNU compiler, but we don't know when it will be publically available.
5536 *** Changes in GDB-4.8:
5538 * HP Precision Architecture supported
5540 GDB now supports HP PA-RISC machines running HPUX. A preliminary
5541 version of this support was available as a set of patches from the
5542 University of Utah. GDB does not support debugging of programs
5543 compiled with the HP compiler, because HP will not document their file
5544 format. Instead, you must use GCC (version 2.3.2 or later) and PA-GAS
5545 (as available from jaguar.cs.utah.edu:/dist/pa-gas.u4.tar.Z).
5547 Many problems in the preliminary version have been fixed.
5549 * Faster and better demangling
5551 We have improved template demangling and fixed numerous bugs in the GNU style
5552 demangler. It can now handle type modifiers such as `static' or `const'. Wide
5553 character types (wchar_t) are now supported. Demangling of each symbol is now
5554 only done once, and is cached when the symbol table for a file is read in.
5555 This results in a small increase in memory usage for C programs, a moderate
5556 increase in memory usage for C++ programs, and a fantastic speedup in
5559 `Cfront' style demangling still doesn't work with AT&T cfront. It was written
5560 from the specifications in the Annotated Reference Manual, which AT&T's
5561 compiler does not actually implement.
5563 * G++ multiple inheritance compiler problem
5565 In the 2.3.2 release of gcc/g++, how the compiler resolves multiple
5566 inheritance lattices was reworked to properly discover ambiguities. We
5567 recently found an example which causes this new algorithm to fail in a
5568 very subtle way, producing bad debug information for those classes.
5569 The file 'gcc.patch' (in this directory) can be applied to gcc to
5570 circumvent the problem. A future GCC release will contain a complete
5573 The previous G++ debug info problem (mentioned below for the gdb-4.7
5574 release) is fixed in gcc version 2.3.2.
5576 * Improved configure script
5578 The `configure' script will now attempt to guess your system type if
5579 you don't supply a host system type. The old scheme of supplying a
5580 host system triplet is preferable over using this. All the magic is
5581 done in the new `config.guess' script. Examine it for details.
5583 We have also brought our configure script much more in line with the FSF's
5584 version. It now supports the --with-xxx options. In particular,
5585 `--with-minimal-bfd' can be used to make the GDB binary image smaller.
5586 The resulting GDB will not be able to read arbitrary object file formats --
5587 only the format ``expected'' to be used on the configured target system.
5588 We hope to make this the default in a future release.
5590 * Documentation improvements
5592 There's new internal documentation on how to modify GDB, and how to
5593 produce clean changes to the code. We implore people to read it
5594 before submitting changes.
5596 The GDB manual uses new, sexy Texinfo conditionals, rather than arcane
5597 M4 macros. The new texinfo.tex is provided in this release. Pre-built
5598 `info' files are also provided. To build `info' files from scratch,
5599 you will need the latest `makeinfo' release, which will be available in
5600 a future texinfo-X.Y release.
5602 *NOTE* The new texinfo.tex can cause old versions of TeX to hang.
5603 We're not sure exactly which versions have this problem, but it has
5604 been seen in 3.0. We highly recommend upgrading to TeX version 3.141
5605 or better. If that isn't possible, there is a patch in
5606 `texinfo/tex3patch' that will modify `texinfo/texinfo.tex' to work
5607 around this problem.
5611 GDB now supports array constants that can be used in expressions typed in by
5612 the user. The syntax is `{element, element, ...}'. Ie: you can now type
5613 `print {1, 2, 3}', and it will build up an array in memory malloc'd in
5616 The new directory `gdb/sparclite' contains a program that demonstrates
5617 how the sparc-stub.c remote stub runs on a Fujitsu SPARClite processor.
5619 * New native hosts supported
5621 HP/PA-RISC under HPUX using GNU tools hppa1.1-hp-hpux
5622 386 CPUs running SCO Unix 3.2v4 i386-unknown-sco3.2v4
5624 * New targets supported
5626 AMD 29k family via UDI a29k-amd-udi or udi29k
5628 * New file formats supported
5630 BFD now supports reading HP/PA-RISC executables (SOM file format?),
5631 HPUX core files, and SCO 3.2v2 core files.
5635 Attaching to processes now works again; thanks for the many bug reports.
5637 We have also stomped on a bunch of core dumps caused by
5638 printf_filtered("%s") problems.
5640 We eliminated a copyright problem on the rpc and ptrace header files
5641 for VxWorks, which was discovered at the last minute during the 4.7
5642 release. You should now be able to build a VxWorks GDB.
5644 You can now interrupt gdb while an attached process is running. This
5645 will cause the attached process to stop, and give control back to GDB.
5647 We fixed problems caused by using too many file descriptors
5648 for reading symbols from object files and libraries. This was
5649 especially a problem for programs that used many (~100) shared
5652 The `step' command now only enters a subroutine if there is line number
5653 information for the subroutine. Otherwise it acts like the `next'
5654 command. Previously, `step' would enter subroutines if there was
5655 any debugging information about the routine. This avoids problems
5656 when using `cc -g1' on MIPS machines.
5658 * Internal improvements
5660 GDB's internal interfaces have been improved to make it easier to support
5661 debugging of multiple languages in the future.
5663 GDB now uses a common structure for symbol information internally.
5664 Minimal symbols (derived from linkage symbols in object files), partial
5665 symbols (from a quick scan of debug information), and full symbols
5666 contain a common subset of information, making it easier to write
5667 shared code that handles any of them.
5669 * New command line options
5671 We now accept --silent as an alias for --quiet.
5675 The memory-mapped-malloc library is now licensed under the GNU Library
5676 General Public License.
5678 *** Changes in GDB-4.7:
5680 * Host/native/target split
5682 GDB has had some major internal surgery to untangle the support for
5683 hosts and remote targets. Now, when you configure GDB for a remote
5684 target, it will no longer load in all of the support for debugging
5685 local programs on the host. When fully completed and tested, this will
5686 ensure that arbitrary host/target combinations are possible.
5688 The primary conceptual shift is to separate the non-portable code in
5689 GDB into three categories. Host specific code is required any time GDB
5690 is compiled on that host, regardless of the target. Target specific
5691 code relates to the peculiarities of the target, but can be compiled on
5692 any host. Native specific code is everything else: it can only be
5693 built when the host and target are the same system. Child process
5694 handling and core file support are two common `native' examples.
5696 GDB's use of /proc for controlling Unix child processes is now cleaner.
5697 It has been split out into a single module under the `target_ops' vector,
5698 plus two native-dependent functions for each system that uses /proc.
5700 * New hosts supported
5702 HP/Apollo 68k (under the BSD domain) m68k-apollo-bsd or apollo68bsd
5703 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
5704 386 CPUs running SCO Unix i386-unknown-scosysv322 or i386sco
5706 * New targets supported
5708 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
5709 68030 and CPU32 m68030-*-*, m68332-*-*
5711 * New native hosts supported
5713 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
5714 (386bsd is not well tested yet)
5715 386 CPUs running SCO Unix i386-unknown-scosysv322 or sco
5717 * New file formats supported
5719 BFD now supports COFF files for the Zilog Z8000 microprocessor. It
5720 supports reading of `a.out.adobe' object files, which are an a.out
5721 format extended with minimal information about multiple sections.
5725 `show copying' is the same as the old `info copying'.
5726 `show warranty' is the same as `info warrantee'.
5727 These were renamed for consistency. The old commands continue to work.
5729 `info handle' is a new alias for `info signals'.
5731 You can now define pre-command hooks, which attach arbitrary command
5732 scripts to any command. The commands in the hook will be executed
5733 prior to the user's command. You can also create a hook which will be
5734 executed whenever the program stops. See gdb.texinfo.
5738 We now deal with Cfront style name mangling, and can even extract type
5739 info from mangled symbols. GDB can automatically figure out which
5740 symbol mangling style your C++ compiler uses.
5742 Calling of methods and virtual functions has been improved as well.
5746 The crash that occured when debugging Sun Ansi-C compiled binaries is
5747 fixed. This was due to mishandling of the extra N_SO stabs output
5750 We also finally got Ultrix 4.2 running in house, and fixed core file
5751 support, with help from a dozen people on the net.
5753 John M. Farrell discovered that the reason that single-stepping was so
5754 slow on all of the Mips based platforms (primarily SGI and DEC) was
5755 that we were trying to demangle and lookup a symbol used for internal
5756 purposes on every instruction that was being stepped through. Changing
5757 the name of that symbol so that it couldn't be mistaken for a C++
5758 mangled symbol sped things up a great deal.
5760 Rich Pixley sped up symbol lookups in general by getting much smarter
5761 about when C++ symbol mangling is necessary. This should make symbol
5762 completion (TAB on the command line) much faster. It's not as fast as
5763 we'd like, but it's significantly faster than gdb-4.6.
5767 A new user controllable variable 'call_scratch_address' can
5768 specify the location of a scratch area to be used when GDB
5769 calls a function in the target. This is necessary because the
5770 usual method of putting the scratch area on the stack does not work
5771 in systems that have separate instruction and data spaces.
5773 We integrated changes to support the 29k UDI (Universal Debugger
5774 Interface), but discovered at the last minute that we didn't have all
5775 of the appropriate copyright paperwork. We are working with AMD to
5776 resolve this, and hope to have it available soon.
5780 We have sped up the remote serial line protocol, especially for targets
5781 with lots of registers. It now supports a new `expedited status' ('T')
5782 message which can be used in place of the existing 'S' status message.
5783 This allows the remote stub to send only the registers that GDB
5784 needs to make a quick decision about single-stepping or conditional
5785 breakpoints, eliminating the need to fetch the entire register set for
5786 each instruction being stepped through.
5788 The GDB remote serial protocol now implements a write-through cache for
5789 registers, only re-reading the registers if the target has run.
5791 There is also a new remote serial stub for SPARC processors. You can
5792 find it in gdb-4.7/gdb/sparc-stub.c. This was written to support the
5793 Fujitsu SPARClite processor, but will run on any stand-alone SPARC
5794 processor with a serial port.
5798 Configure.in files have become much easier to read and modify. A new
5799 `table driven' format makes it more obvious what configurations are
5800 supported, and what files each one uses.
5804 There is a new opcodes library which will eventually contain all of the
5805 disassembly routines and opcode tables. At present, it only contains
5806 Sparc and Z8000 routines. This will allow the assembler, debugger, and
5807 disassembler (binutils/objdump) to share these routines.
5809 The libiberty library is now copylefted under the GNU Library General
5810 Public License. This allows more liberal use, and was done so libg++
5811 can use it. This makes no difference to GDB, since the Library License
5812 grants all the rights from the General Public License.
5816 The file gdb-4.7/gdb/doc/stabs.texinfo is a (relatively) complete
5817 reference to the stabs symbol info used by the debugger. It is (as far
5818 as we know) the only published document on this fascinating topic. We
5819 encourage you to read it, compare it to the stabs information on your
5820 system, and send improvements on the document in general (to
5821 bug-gdb@prep.ai.mit.edu).
5823 And, of course, many bugs have been fixed.
5826 *** Changes in GDB-4.6:
5828 * Better support for C++ function names
5830 GDB now accepts as input the "demangled form" of C++ overloaded function
5831 names and member function names, and can do command completion on such names
5832 (using TAB, TAB-TAB, and ESC-?). The names have to be quoted with a pair of
5833 single quotes. Examples are 'func (int, long)' and 'obj::operator==(obj&)'.
5834 Make use of command completion, it is your friend.
5836 GDB also now accepts a variety of C++ mangled symbol formats. They are
5837 the GNU g++ style, the Cfront (ARM) style, and the Lucid (lcc) style.
5838 You can tell GDB which format to use by doing a 'set demangle-style {gnu,
5839 lucid, cfront, auto}'. 'gnu' is the default. Do a 'set demangle-style foo'
5840 for the list of formats.
5842 * G++ symbol mangling problem
5844 Recent versions of gcc have a bug in how they emit debugging information for
5845 C++ methods (when using dbx-style stabs). The file 'gcc.patch' (in this
5846 directory) can be applied to gcc to fix the problem. Alternatively, if you
5847 can't fix gcc, you can #define GCC_MANGLE_BUG when compling gdb/symtab.c. The
5848 usual symptom is difficulty with setting breakpoints on methods. GDB complains
5849 about the method being non-existent. (We believe that version 2.2.2 of GCC has
5852 * New 'maintenance' command
5854 All of the commands related to hacking GDB internals have been moved out of
5855 the main command set, and now live behind the 'maintenance' command. This
5856 can also be abbreviated as 'mt'. The following changes were made:
5858 dump-me -> maintenance dump-me
5859 info all-breakpoints -> maintenance info breakpoints
5860 printmsyms -> maintenance print msyms
5861 printobjfiles -> maintenance print objfiles
5862 printpsyms -> maintenance print psymbols
5863 printsyms -> maintenance print symbols
5865 The following commands are new:
5867 maintenance demangle Call internal GDB demangler routine to
5868 demangle a C++ link name and prints the result.
5869 maintenance print type Print a type chain for a given symbol
5871 * Change to .gdbinit file processing
5873 We now read the $HOME/.gdbinit file before processing the argv arguments
5874 (e.g. reading symbol files or core files). This allows global parameters to
5875 be set, which will apply during the symbol reading. The ./.gdbinit is still
5876 read after argv processing.
5878 * New hosts supported
5880 Solaris-2.0 !!! sparc-sun-solaris2 or sun4sol2
5882 GNU/Linux support i386-unknown-linux or linux
5884 We are also including code to support the HP/PA running BSD and HPUX. This
5885 is almost guaranteed not to work, as we didn't have time to test or build it
5886 for this release. We are including it so that the more adventurous (or
5887 masochistic) of you can play with it. We also had major problems with the
5888 fact that the compiler that we got from HP doesn't support the -g option.
5891 * New targets supported
5893 Hitachi H8/300 h8300-hitachi-hms or h8300hms
5895 * More smarts about finding #include files
5897 GDB now remembers the compilation directory for all include files, and for
5898 all files from which C is generated (like yacc and lex sources). This
5899 greatly improves GDB's ability to find yacc/lex sources, and include files,
5900 especially if you are debugging your program from a directory different from
5901 the one that contains your sources.
5903 We also fixed a bug which caused difficulty with listing and setting
5904 breakpoints in include files which contain C code. (In the past, you had to
5905 try twice in order to list an include file that you hadn't looked at before.)
5907 * Interesting infernals change
5909 GDB now deals with arbitrary numbers of sections, where the symbols for each
5910 section must be relocated relative to that section's landing place in the
5911 target's address space. This work was needed to support ELF with embedded
5912 stabs used by Solaris-2.0.
5914 * Bug fixes (of course!)
5916 There have been loads of fixes for the following things:
5917 mips, rs6000, 29k/udi, m68k, g++, type handling, elf/dwarf, m88k,
5918 i960, stabs, DOS(GO32), procfs, etc...
5920 See the ChangeLog for details.
5922 *** Changes in GDB-4.5:
5924 * New machines supported (host and target)
5926 IBM RS6000 running AIX rs6000-ibm-aix or rs6000
5928 SGI Irix-4.x mips-sgi-irix4 or iris4
5930 * New malloc package
5932 GDB now uses a new memory manager called mmalloc, based on gmalloc.
5933 Mmalloc is capable of handling mutiple heaps of memory. It is also
5934 capable of saving a heap to a file, and then mapping it back in later.
5935 This can be used to greatly speedup the startup of GDB by using a
5936 pre-parsed symbol table which lives in a mmalloc managed heap. For
5937 more details, please read mmalloc/mmalloc.texi.
5941 The 'info proc' command (SVR4 only) has been enhanced quite a bit. See
5942 'help info proc' for details.
5944 * MIPS ecoff symbol table format
5946 The code that reads MIPS symbol table format is now supported on all hosts.
5947 Thanks to MIPS for releasing the sym.h and symconst.h files to make this
5950 * File name changes for MS-DOS
5952 Many files in the config directories have been renamed to make it easier to
5953 support GDB on MS-DOSe systems (which have very restrictive file name
5954 conventions :-( ). MS-DOSe host support (under DJ Delorie's GO32
5955 environment) is close to working but has some remaining problems. Note
5956 that debugging of DOS programs is not supported, due to limitations
5957 in the ``operating system'', but it can be used to host cross-debugging.
5959 * Cross byte order fixes
5961 Many fixes have been made to support cross debugging of Sparc and MIPS
5962 targets from hosts whose byte order differs.
5964 * New -mapped and -readnow options
5966 If memory-mapped files are available on your system through the 'mmap'
5967 system call, you can use the -mapped option on the `file' or
5968 `symbol-file' commands to cause GDB to write the symbols from your
5969 program into a reusable file. If the program you are debugging is
5970 called `/path/fred', the mapped symbol file will be `./fred.syms'.
5971 Future GDB debugging sessions will notice the presence of this file,
5972 and will quickly map in symbol information from it, rather than reading
5973 the symbol table from the executable program. Using the '-mapped'
5974 option in a GDB `file' or `symbol-file' command has the same effect as
5975 starting GDB with the '-mapped' command-line option.
5977 You can cause GDB to read the entire symbol table immediately by using
5978 the '-readnow' option with any of the commands that load symbol table
5979 information (or on the GDB command line). This makes the command
5980 slower, but makes future operations faster.
5982 The -mapped and -readnow options are typically combined in order to
5983 build a `fred.syms' file that contains complete symbol information.
5984 A simple GDB invocation to do nothing but build a `.syms' file for future
5987 gdb -batch -nx -mapped -readnow programname
5989 The `.syms' file is specific to the host machine on which GDB is run.
5990 It holds an exact image of GDB's internal symbol table. It cannot be
5991 shared across multiple host platforms.
5993 * longjmp() handling
5995 GDB is now capable of stepping and nexting over longjmp(), _longjmp(), and
5996 siglongjmp() without losing control. This feature has not yet been ported to
5997 all systems. It currently works on many 386 platforms, all MIPS-based
5998 platforms (SGI, DECstation, etc), and Sun3/4.
6002 Preliminary work has been put in to support the new Solaris OS from Sun. At
6003 this time, it can control and debug processes, but it is not capable of
6008 As always, many many bug fixes. The major areas were with g++, and mipsread.
6009 People using the MIPS-based platforms should experience fewer mysterious
6010 crashes and trashed symbol tables.
6012 *** Changes in GDB-4.4:
6014 * New machines supported (host and target)
6016 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
6018 BSD Reno on Vax vax-dec-bsd
6019 Ultrix on Vax vax-dec-ultrix
6021 * New machines supported (target)
6023 AMD 29000 embedded, using EBMON a29k-none-none
6027 GDB continues to improve its handling of C++. `References' work better.
6028 The demangler has also been improved, and now deals with symbols mangled as
6029 per the Annotated C++ Reference Guide.
6031 GDB also now handles `stabs' symbol information embedded in MIPS
6032 `ecoff' symbol tables. Since the ecoff format was not easily
6033 extensible to handle new languages such as C++, this appeared to be a
6034 good way to put C++ debugging info into MIPS binaries. This option
6035 will be supported in the GNU C compiler, version 2, when it is
6038 * New features for SVR4
6040 GDB now handles SVR4 shared libraries, in the same fashion as SunOS
6041 shared libraries. Debugging dynamically linked programs should present
6042 only minor differences from debugging statically linked programs.
6044 The `info proc' command will print out information about any process
6045 on an SVR4 system (including the one you are debugging). At the moment,
6046 it prints the address mappings of the process.
6048 If you bring up GDB on another SVR4 system, please send mail to
6049 bug-gdb@prep.ai.mit.edu to let us know what changes were reqired (if any).
6051 * Better dynamic linking support in SunOS
6053 Reading symbols from shared libraries which contain debugging symbols
6054 now works properly. However, there remain issues such as automatic
6055 skipping of `transfer vector' code during function calls, which
6056 make it harder to debug code in a shared library, than to debug the
6057 same code linked statically.
6061 GDB is now using the latest `getopt' routines from the FSF. This
6062 version accepts the -- prefix for options with long names. GDB will
6063 continue to accept the old forms (-option and +option) as well.
6064 Various single letter abbreviations for options have been explicity
6065 added to the option table so that they won't get overshadowed in the
6066 future by other options that begin with the same letter.
6070 The `cleanup_undefined_types' bug that many of you noticed has been squashed.
6071 Many assorted bugs have been handled. Many more remain to be handled.
6072 See the various ChangeLog files (primarily in gdb and bfd) for details.
6075 *** Changes in GDB-4.3:
6077 * New machines supported (host and target)
6079 Amiga 3000 running Amix m68k-cbm-svr4 or amix
6080 NCR 3000 386 running SVR4 i386-ncr-svr4 or ncr3000
6081 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
6083 * Almost SCO Unix support
6085 We had hoped to support:
6086 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
6087 (except for core file support), but we discovered very late in the release
6088 that it has problems with process groups that render gdb unusable. Sorry
6089 about that. I encourage people to fix it and post the fixes.
6091 * Preliminary ELF and DWARF support
6093 GDB can read ELF object files on System V Release 4, and can handle
6094 debugging records for C, in DWARF format, in ELF files. This support
6095 is preliminary. If you bring up GDB on another SVR4 system, please
6096 send mail to bug-gdb@prep.ai.mit.edu to let us know what changes were
6101 GDB now uses the latest `readline' library. One user-visible change
6102 is that two tabs will list possible command completions, which previously
6103 required typing M-? (meta-question mark, or ESC ?).
6107 The `stepi' bug that many of you noticed has been squashed.
6108 Many bugs in C++ have been handled. Many more remain to be handled.
6109 See the various ChangeLog files (primarily in gdb and bfd) for details.
6111 * State of the MIPS world (in case you wondered):
6113 GDB can understand the symbol tables emitted by the compilers
6114 supplied by most vendors of MIPS-based machines, including DEC. These
6115 symbol tables are in a format that essentially nobody else uses.
6117 Some versions of gcc come with an assembler post-processor called
6118 mips-tfile. This program is required if you want to do source-level
6119 debugging of gcc-compiled programs. I believe FSF does not ship
6120 mips-tfile with gcc version 1, but it will eventually come with gcc
6123 Debugging of g++ output remains a problem. g++ version 1.xx does not
6124 really support it at all. (If you're lucky, you should be able to get
6125 line numbers and stack traces to work, but no parameters or local
6126 variables.) With some work it should be possible to improve the
6129 When gcc version 2 is released, you will have somewhat better luck.
6130 However, even then you will get confusing results for inheritance and
6133 We will eventually provide full debugging of g++ output on
6134 DECstations. This will probably involve some kind of stabs-in-ecoff
6135 encapulation, but the details have not been worked out yet.
6138 *** Changes in GDB-4.2:
6140 * Improved configuration
6142 Only one copy of `configure' exists now, and it is not self-modifying.
6143 Porting BFD is simpler.
6147 The `step' and `next' commands now only stop at the first instruction
6148 of a source line. This prevents the multiple stops that used to occur
6149 in switch statements, for-loops, etc. `Step' continues to stop if a
6150 function that has debugging information is called within the line.
6154 Lots of small bugs fixed. More remain.
6156 * New host supported (not target)
6158 Intel 386 PC clone running Mach i386-none-mach
6161 *** Changes in GDB-4.1:
6163 * Multiple source language support
6165 GDB now has internal scaffolding to handle several source languages.
6166 It determines the type of each source file from its filename extension,
6167 and will switch expression parsing and number formatting to match the
6168 language of the function in the currently selected stack frame.
6169 You can also specifically set the language to be used, with
6170 `set language c' or `set language modula-2'.
6174 GDB now has preliminary support for the GNU Modula-2 compiler,
6175 currently under development at the State University of New York at
6176 Buffalo. Development of both GDB and the GNU Modula-2 compiler will
6177 continue through the fall of 1991 and into 1992.
6179 Other Modula-2 compilers are currently not supported, and attempting to
6180 debug programs compiled with them will likely result in an error as the
6181 symbol table is read. Feel free to work on it, though!
6183 There are hooks in GDB for strict type checking and range checking,
6184 in the `Modula-2 philosophy', but they do not currently work.
6188 GDB can now write to executable and core files (e.g. patch
6189 a variable's value). You must turn this switch on, specify
6190 the file ("exec foo" or "core foo"), *then* modify it, e.g.
6191 by assigning a new value to a variable. Modifications take
6194 * Automatic SunOS shared library reading
6196 When you run your program, GDB automatically determines where its
6197 shared libraries (if any) have been loaded, and reads their symbols.
6198 The `share' command is no longer needed. This also works when
6199 examining core files.
6203 You can specify the number of lines that the `list' command shows.
6206 * New machines supported (host and target)
6208 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
6209 Sony NEWS (68K) running NEWSOS 3.x: m68k-sony-sysv or news
6210 Ultracomputer (29K) running Sym1: a29k-nyu-sym1 or ultra3
6212 * New hosts supported (not targets)
6214 IBM RT/PC: romp-ibm-aix or rtpc
6216 * New targets supported (not hosts)
6218 AMD 29000 embedded with COFF a29k-none-coff
6219 AMD 29000 embedded with a.out a29k-none-aout
6220 Ultracomputer remote kernel debug a29k-nyu-kern
6222 * New remote interfaces
6228 *** Changes in GDB-4.0:
6232 Wide output is wrapped at good places to make the output more readable.
6234 Gdb now supports cross-debugging from a host machine of one type to a
6235 target machine of another type. Communication with the target system
6236 is over serial lines. The ``target'' command handles connecting to the
6237 remote system; the ``load'' command will download a program into the
6238 remote system. Serial stubs for the m68k and i386 are provided. Gdb
6239 also supports debugging of realtime processes running under VxWorks,
6240 using SunRPC Remote Procedure Calls over TCP/IP to talk to a debugger
6241 stub on the target system.
6243 New CPUs supported include the AMD 29000 and Intel 960.
6245 GDB now reads object files and symbol tables via a ``binary file''
6246 library, which allows a single copy of GDB to debug programs of multiple
6247 object file types such as a.out and coff.
6249 There is now a GDB reference card in "doc/refcard.tex". (Make targets
6250 refcard.dvi and refcard.ps are available to format it).
6253 * Control-Variable user interface simplified
6255 All variables that control the operation of the debugger can be set
6256 by the ``set'' command, and displayed by the ``show'' command.
6258 For example, ``set prompt new-gdb=>'' will change your prompt to new-gdb=>.
6259 ``Show prompt'' produces the response:
6260 Gdb's prompt is new-gdb=>.
6262 What follows are the NEW set commands. The command ``help set'' will
6263 print a complete list of old and new set commands. ``help set FOO''
6264 will give a longer description of the variable FOO. ``show'' will show
6265 all of the variable descriptions and their current settings.
6267 confirm on/off: Enables warning questions for operations that are
6268 hard to recover from, e.g. rerunning the program while
6269 it is already running. Default is ON.
6271 editing on/off: Enables EMACS style command line editing
6272 of input. Previous lines can be recalled with
6273 control-P, the current line can be edited with control-B,
6274 you can search for commands with control-R, etc.
6277 history filename NAME: NAME is where the gdb command history
6278 will be stored. The default is .gdb_history,
6279 or the value of the environment variable
6282 history size N: The size, in commands, of the command history. The
6283 default is 256, or the value of the environment variable
6286 history save on/off: If this value is set to ON, the history file will
6287 be saved after exiting gdb. If set to OFF, the
6288 file will not be saved. The default is OFF.
6290 history expansion on/off: If this value is set to ON, then csh-like
6291 history expansion will be performed on
6292 command line input. The default is OFF.
6294 radix N: Sets the default radix for input and output. It can be set
6295 to 8, 10, or 16. Note that the argument to "radix" is interpreted
6296 in the current radix, so "set radix 10" is always a no-op.
6298 height N: This integer value is the number of lines on a page. Default
6299 is 24, the current `stty rows'' setting, or the ``li#''
6300 setting from the termcap entry matching the environment
6303 width N: This integer value is the number of characters on a line.
6304 Default is 80, the current `stty cols'' setting, or the ``co#''
6305 setting from the termcap entry matching the environment
6308 Note: ``set screensize'' is obsolete. Use ``set height'' and
6309 ``set width'' instead.
6311 print address on/off: Print memory addresses in various command displays,
6312 such as stack traces and structure values. Gdb looks
6313 more ``symbolic'' if you turn this off; it looks more
6314 ``machine level'' with it on. Default is ON.
6316 print array on/off: Prettyprint arrays. New convenient format! Default
6319 print demangle on/off: Print C++ symbols in "source" form if on,
6322 print asm-demangle on/off: Same, for assembler level printouts
6325 print vtbl on/off: Prettyprint C++ virtual function tables. Default is OFF.
6328 * Support for Epoch Environment.
6330 The epoch environment is a version of Emacs v18 with windowing. One
6331 new command, ``inspect'', is identical to ``print'', except that if you
6332 are running in the epoch environment, the value is printed in its own
6336 * Support for Shared Libraries
6338 GDB can now debug programs and core files that use SunOS shared libraries.
6339 Symbols from a shared library cannot be referenced
6340 before the shared library has been linked with the program (this
6341 happens after you type ``run'' and before the function main() is entered).
6342 At any time after this linking (including when examining core files
6343 from dynamically linked programs), gdb reads the symbols from each
6344 shared library when you type the ``sharedlibrary'' command.
6345 It can be abbreviated ``share''.
6347 sharedlibrary REGEXP: Load shared object library symbols for files
6348 matching a unix regular expression. No argument
6349 indicates to load symbols for all shared libraries.
6351 info sharedlibrary: Status of loaded shared libraries.
6356 A watchpoint stops execution of a program whenever the value of an
6357 expression changes. Checking for this slows down execution
6358 tremendously whenever you are in the scope of the expression, but is
6359 quite useful for catching tough ``bit-spreader'' or pointer misuse
6360 problems. Some machines such as the 386 have hardware for doing this
6361 more quickly, and future versions of gdb will use this hardware.
6363 watch EXP: Set a watchpoint (breakpoint) for an expression.
6365 info watchpoints: Information about your watchpoints.
6367 delete N: Deletes watchpoint number N (same as breakpoints).
6368 disable N: Temporarily turns off watchpoint number N (same as breakpoints).
6369 enable N: Re-enables watchpoint number N (same as breakpoints).
6372 * C++ multiple inheritance
6374 When used with a GCC version 2 compiler, GDB supports multiple inheritance
6377 * C++ exception handling
6379 Gdb now supports limited C++ exception handling. Besides the existing
6380 ability to breakpoint on an exception handler, gdb can breakpoint on
6381 the raising of an exception (before the stack is peeled back to the
6384 catch FOO: If there is a FOO exception handler in the dynamic scope,
6385 set a breakpoint to catch exceptions which may be raised there.
6386 Multiple exceptions (``catch foo bar baz'') may be caught.
6388 info catch: Lists all exceptions which may be caught in the
6389 current stack frame.
6392 * Minor command changes
6394 The command ``call func (arg, arg, ...)'' now acts like the print
6395 command, except it does not print or save a value if the function's result
6396 is void. This is similar to dbx usage.
6398 The ``up'' and ``down'' commands now always print the frame they end up
6399 at; ``up-silently'' and `down-silently'' can be used in scripts to change
6400 frames without printing.
6402 * New directory command
6404 'dir' now adds directories to the FRONT of the source search path.
6405 The path starts off empty. Source files that contain debug information
6406 about the directory in which they were compiled can be found even
6407 with an empty path; Sun CC and GCC include this information. If GDB can't
6408 find your source file in the current directory, type "dir .".
6410 * Configuring GDB for compilation
6412 For normal use, type ``./configure host''. See README or gdb.texinfo
6415 GDB now handles cross debugging. If you are remotely debugging between
6416 two different machines, type ``./configure host -target=targ''.
6417 Host is the machine where GDB will run; targ is the machine
6418 where the program that you are debugging will run.
projects / external / binutils.git / blob